System Information
Operating system: Windows 10
Graphics card: Nvidia GTX 1070

Blender Version
Broken:
2.82 Beta, 507a331f0182, blender2.8, 2020-01-27

Short description of error
After undoing any change, every particle system in the scene resets its orientation axis. To fix this, you have to manually change the orientation axis to something else and back again. There may be other situations where the particle orientation gets reset, but this one is easily reproducible.

Exact steps for others to reproduce the error

1. Open the attached file
2. Set the ParticleSettings>Rotation>Orientation Axis to Global Z
3. Shift-A and add a cube (or any change at all to the scene)
4. Ctrl-Z

The particles are not longer aligned on the global z-axis.

Alternatively, it also breaks if you:

1. Open the attached file
2. Set the ParticleSettings>Rotation>Orientation Axis to Global Z
3. Save the file
4. Close and reopen the file