dials.sequence_to_stills without a scan-varying model fails

[dagewa]

Not sure if this is a bug or a usage question. This is what I tried:

$ dials.sequence_to_stills indexed.expt indexed.refl
The following parameters have been modified:

input {
  experiments = indexed.expt
  reflections = indexed.refl
}

Traceback (most recent call last):
  File "/home/fcx32934/sw/cctbx/build/../modules/dials/src/dials/command_line/sequence_to_stills.py", line 244, in <module>
    run()
  File "/home/fcx32934/sw/cctbx/conda_base/lib/python3.10/contextlib.py", line 79, in inner
    return func(*args, **kwds)
  File "/home/fcx32934/sw/cctbx/build/../modules/dials/src/dials/command_line/sequence_to_stills.py", line 235, in run
    (new_experiments, new_reflections) = sequence_to_stills(
  File "/home/fcx32934/sw/cctbx/build/../modules/dials/src/dials/command_line/sequence_to_stills.py", line 129, in sequence_to_stills
    * matrix.sqr(experiment.crystal.get_A_at_scan_point(i_array))
RuntimeError: Please report this error to [email protected]: dxtbx Internal Error: /home/fcx32934/sw/cctbx/modules/dxtbx/src/dxtbx/model/crystal.h(553): DXTBX_ASSERT(index < A_at_scan_points_.size()) failure.

Is dials.sequence_to_stills supposed to work on indexed.{expt,refl}?