diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 31583e6..26fad73 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -8,8 +8,8 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        gemfile: [rails_7_0.gemfile, rails_head.gemfile]
-        ruby_version: [2.7, 3.0]
+        gemfile: [rails_7_1.gemfile, rails_head.gemfile]
+        ruby_version: [2.7, 3.0, 3.1, 3.2]
     env:
       BUNDLE_GEMFILE: gemfiles/${{ matrix.gemfile }}
       CC_TEST_REPORTER_ID: 7196b4aa257fde33f24463218af32db6a6efd23d9148204822f757fa614a093e
diff --git a/README.md b/README.md
index aa65f24..f3feb2b 100644
--- a/README.md
+++ b/README.md
@@ -16,6 +16,7 @@ gem 'active_storage_base64'
 ## Compatibility
 Rails Version | ActiveStorageBase64 Version
 --------------|-----------------------------
+7.1.x         | 3.0.x
 7.0.x         | 2.0.x
 6.1.x         | 1.2.x
 6.0.x         | 1.1.x
diff --git a/active_storage_base64.gemspec b/active_storage_base64.gemspec
index ee1b2fe..a3a0deb 100644
--- a/active_storage_base64.gemspec
+++ b/active_storage_base64.gemspec
@@ -1,6 +1,6 @@
 Gem::Specification.new do |s|
   s.name = 'active_storage_base64'
-  s.version = '2.0.0'
+  s.version = '3.0.0'
   s.summary = 'Base64 support for ActiveStorage'
   s.description = s.summary
 
@@ -15,7 +15,7 @@ Gem::Specification.new do |s|
   s.required_ruby_version = '>= 2.7.0'
 
   # Dependencies
-  s.add_dependency 'rails', '>= 7.0'
+  s.add_dependency 'rails', '>= 7.1'
 
   # Development dependencies
   s.add_development_dependency 'pry-rails', '~> 0.3.6'
diff --git a/bug_report_template.rb b/bug_report_template.rb
index a992247..d9b3ee5 100644
--- a/bug_report_template.rb
+++ b/bug_report_template.rb
@@ -8,9 +8,9 @@
   git_source(:github) { |repo| "https://github.com/#{repo}.git" }
 
   # Activate the gem you are reporting the issue against.
-  gem 'rails', '~> 7.0'
+  gem 'rails', '~> 7.1'
   gem 'sqlite3'
-  gem 'active_storage_base64', '~> 2.0.0'
+  gem 'active_storage_base64', '~> 3.0.0'
 end
 
 require 'active_record/railtie'
diff --git a/gemfiles/rails_7_0.gemfile b/gemfiles/rails_7_1.gemfile
similarity index 68%
rename from gemfiles/rails_7_0.gemfile
rename to gemfiles/rails_7_1.gemfile
index 998d87a..2ce3117 100644
--- a/gemfiles/rails_7_0.gemfile
+++ b/gemfiles/rails_7_1.gemfile
@@ -1,5 +1,5 @@
 source 'https://rubygems.org'
 
-gem 'rails', '~> 7.0.0'
+gem 'rails', '~> 7.1.0'
 
 gemspec path: '..'
diff --git a/lib/active_storage_support/support_for_base64.rb b/lib/active_storage_support/support_for_base64.rb
index 41264d1..47a6984 100644
--- a/lib/active_storage_support/support_for_base64.rb
+++ b/lib/active_storage_support/support_for_base64.rb
@@ -17,7 +17,7 @@ def #{name}
 
           def #{name}=(attachable)
             attachment_changes["#{name}"] =
-              if attachable.nil?
+              if attachable.nil? || attachable == ""
                 ActiveStorage::Attached::Changes::DeleteOne.new("#{name}", self)
               else
                 ActiveStorage::Attached::Changes::CreateOne.new(
@@ -39,28 +39,15 @@ def #{name}
           end
 
           def #{name}=(attachables)
-            if ActiveStorage.replace_on_assign_to_many
-              attachment_changes["#{name}"] =
-                if Array(attachables).none?
-                  ActiveStorage::Attached::Changes::DeleteMany.new("#{name}", self)
-                else
-                  ActiveStorage::Attached::Changes::CreateMany.new(
-                    "#{name}", self, ActiveStorageSupport::Base64Many.from_base64(attachables)
-                  )
-                end
-            else
-              ActiveSupport::Deprecation.warn \
-                "config.active_storage.replace_on_assign_to_many is deprecated and will be removed in Rails 7.1. " \
-                "Make sure that your code works well with config.active_storage.replace_on_assign_to_many set to true before upgrading. " \
-                "To append new attachables to the Active Storage association, prefer using `attach`. " \
-                "Using association setter would result in purging the existing attached attachments and replacing them with new ones."
+            attachables = Array(attachables).compact_blank
+            pending_uploads = attachment_changes["#{name}"].try(:pending_uploads)
 
-              if Array(attachables).any?
-                attachment_changes["#{name}"] =
-                  ActiveStorage::Attached::Changes::CreateMany.new(
-                    "#{name}", self, #{name}.blobs + ActiveStorageSupport::Base64Many.from_base64(attachables)
-                  )
-              end
+            attachment_changes["#{name}"] = if attachables.none?
+              ActiveStorage::Attached::Changes::DeleteMany.new("#{name}", self)
+            else
+              ActiveStorage::Attached::Changes::CreateMany.new(
+                "#{name}", self, ActiveStorageSupport::Base64Many.from_base64(attachables), pending_uploads: pending_uploads
+              )
             end
           end
         CODE
diff --git a/spec/user_base64_spec.rb b/spec/user_base64_spec.rb
index 2d6f5e2..374d3ed 100644
--- a/spec/user_base64_spec.rb
+++ b/spec/user_base64_spec.rb
@@ -446,14 +446,14 @@
           context 'when it is called with only one picture' do
             context 'when only data is specified' do
               it 'attaches a picture to the user' do
-                user.pictures = base64_data
+                user.pictures = [base64_data]
                 user.save
 
                 expect(user.pictures.attached?).to be
               end
 
               it 'attached file matches attachment file' do
-                user.pictures = base64_data
+                user.pictures = [base64_data]
                 user.save
 
                 expect(
@@ -465,7 +465,7 @@
 
             context 'when filename is specified' do
               it 'assigns the specified filename' do
-                user.pictures = data_with_filename
+                user.pictures = [data_with_filename]
                 user.save
 
                 expect(user.pictures.first.filename.to_s).to eq(filename)
@@ -531,14 +531,14 @@
           context 'when it is called with only one picture' do
             context 'when only data is specified' do
               it 'attaches a picture to the user' do
-                user.pictures = base64_data
+                user.pictures = [base64_data]
                 user.save
 
                 expect(user.pictures.attached?).to be
               end
 
               it 'attached file matches attachment file' do
-                user.pictures = base64_data
+                user.pictures = [base64_data]
                 user.save
 
                 expect(
@@ -550,7 +550,7 @@
 
             context 'when filename is specified' do
               it 'assigns the specified filename' do
-                user.pictures = data_with_filename
+                user.pictures = [data_with_filename]
                 user.save
 
                 expect(user.pictures.first.filename.to_s).to eq(filename)
@@ -610,13 +610,13 @@
         context 'when a single picture is passed' do
           context 'when only data is specified' do
             it 'attaches a picture' do
-              user = User.create!(pictures: base64_data)
+              user = User.create!(pictures: [base64_data])
 
               expect(user.pictures.attached?).to be
             end
 
             it 'attached file matches attachment file' do
-              user = User.create!(pictures: base64_data)
+              user = User.create!(pictures: [base64_data])
 
               expect(
                 File.open(ActiveStorage::Blob.service.send(:path_for,
@@ -627,7 +627,7 @@
 
           context 'when a filename is specified' do
             it 'assigns the specified filename' do
-              user = User.create!(pictures: data_with_filename)
+              user = User.create!(pictures: [data_with_filename])
 
               expect(user.pictures.first.filename.to_s).to eq(filename)
             end
@@ -662,13 +662,13 @@
         context 'when a single picture is passed' do
           context 'when only data is specified' do
             it 'attaches a picture' do
-              user = User.create!(pictures: base64_data)
+              user = User.create!(pictures: [base64_data])
 
               expect(user.pictures.attached?).to be
             end
 
             it 'attached file matches attachment file' do
-              user = User.create!(pictures: base64_data)
+              user = User.create!(pictures: [base64_data])
 
               expect(
                 File.open(ActiveStorage::Blob.service.send(:path_for,
@@ -679,7 +679,7 @@
 
           context 'when a filename is specified' do
             it 'assigns the specified filename' do
-              user = User.create!(pictures: data_with_filename)
+              user = User.create!(pictures: [data_with_filename])
 
               expect(user.pictures.first.filename.to_s).to eq(filename)
             end
@@ -704,7 +704,7 @@
           end
 
           context 'when user has only one picture attached' do
-            let(:user) { User.create!(pictures: base64_data) }
+            let(:user) { User.create!(pictures: [base64_data]) }
 
             context 'when the user wants to remove the picture' do
               it 'removes the picture' do
@@ -747,38 +747,10 @@
               end
             end
 
-            context 'when replacing on assign' do
-              before do
-                @previous = ActiveStorage.replace_on_assign_to_many
-                ActiveStorage.replace_on_assign_to_many = true
-              end
-
-              after do
-                ActiveStorage.replace_on_assign_to_many = @previous
-              end
-
-              it 'updates the existing record replacing attachments' do
-                user.pictures = pictures_attachments
-                user.save
-                expect(user.pictures.count).to eq(2)
-              end
-            end
-
-            context 'when appending on assign' do
-              before do
-                @previous = ActiveStorage.replace_on_assign_to_many
-                ActiveStorage.replace_on_assign_to_many = false
-              end
-
-              after do
-                ActiveStorage.replace_on_assign_to_many = @previous
-              end
-
-              it 'updates the existing record appending the new attachments' do
-                user.pictures = pictures_attachments
-                user.save
-                expect(user.pictures.count).to eq(4)
-              end
+            it 'updates the existing record replacing attachments' do
+              user.pictures = pictures_attachments
+              user.save
+              expect(user.pictures.count).to eq(2)
             end
           end
         end
@@ -798,7 +770,7 @@
             params.permit(:data)
           end
           context 'when user has only one picture attached' do
-            let(:user) { User.create!(pictures: base64_data) }
+            let(:user) { User.create!(pictures: [base64_data]) }
 
             context 'when the user wants to remove the picture' do
               it 'removes the picture' do
@@ -841,38 +813,10 @@
               end
             end
 
-            context 'when replacing on assign' do
-              before do
-                @previous = ActiveStorage.replace_on_assign_to_many
-                ActiveStorage.replace_on_assign_to_many = true
-              end
-
-              after do
-                ActiveStorage.replace_on_assign_to_many = @previous
-              end
-
-              it 'updates the existing record replacing attachments' do
-                user.pictures = pictures_attachments
-                user.save
-                expect(user.pictures.count).to eq(2)
-              end
-            end
-
-            context 'when appending on assign' do
-              before do
-                @previous = ActiveStorage.replace_on_assign_to_many
-                ActiveStorage.replace_on_assign_to_many = false
-              end
-
-              after do
-                ActiveStorage.replace_on_assign_to_many = @previous
-              end
-
-              it 'updates the existing record appending the new attachments' do
-                user.pictures = pictures_attachments
-                user.save
-                expect(user.pictures.count).to eq(4)
-              end
+            it 'updates the existing record replacing attachments' do
+              user.pictures = pictures_attachments
+              user.save
+              expect(user.pictures.count).to eq(2)
             end
           end
         end
@@ -880,7 +824,7 @@
     end
 
     context 'when using a variant' do
-      let(:user) { User.create!(pictures: base64_data) }
+      let(:user) { User.create!(pictures: [base64_data]) }
 
       it 'returns a link' do
         url = rails_url.rails_blob_url(user.pictures.first.variant(:thumb).processed)
diff --git a/spec/user_file_spec.rb b/spec/user_file_spec.rb
index ffdc384..ecfc184 100644
--- a/spec/user_file_spec.rb
+++ b/spec/user_file_spec.rb
@@ -174,14 +174,14 @@
       context 'when "user.pictures=" is called' do
         context 'when it is called with only one picture' do
           it 'attaches a picture to the user' do
-            user.pictures = file
+            user.pictures = [file]
             user.save
 
             expect(user.pictures.attached?).to be
           end
 
           it 'assigns the specified filename' do
-            user.pictures = file
+            user.pictures = [file]
             user.save
 
             expect(user.pictures.first.filename.to_s).to eq(filename)
@@ -191,14 +191,14 @@
         context 'when it is called with more than one picture' do
           context 'when called with an array' do
             it 'attaches an array of pictures to the user' do
-              user.pictures = pictures_attachments
+              user.pictures = [pictures_attachments]
               user.save
 
               expect(user.pictures.count).to eq(2)
             end
 
             it 'assigns the specified filename' do
-              user.pictures = pictures_attachments
+              user.pictures = [pictures_attachments]
               user.save
 
               expect(user.pictures.first.filename).to eq(filename)
@@ -228,13 +228,13 @@
       context 'when pictures are passed as a hash parameter' do
         context 'when a single picture is passed' do
           it 'attaches a picture' do
-            user = User.create!(pictures: file)
+            user = User.create!(pictures: [file])
 
             expect(user.pictures.attached?).to be
           end
 
           it 'assigns the specified filename' do
-            user = User.create!(pictures: file)
+            user = User.create!(pictures: [file])
 
             expect(user.pictures.first.filename).to eq(filename)
           end
@@ -258,7 +258,7 @@
 
       context 'when user already has pictures attached' do
         context 'when user has only one picture attached' do
-          let(:user) { User.create!(pictures: file) }
+          let(:user) { User.create!(pictures: [file]) }
 
           context 'when the user wants to remove the picture' do
             it 'removes the picture' do