Mass legal employer change is updating assignment category

Summary:

If a person has “Part time” under Fulltime or Part time field and “Regular” under Regular or Temporary and Assignment category is "blank", once MLEC is performed , Assignment category gets changes to “Part-time Regular”, this behavior is present regardless of their Assignment status (whether Assignment status is Active or Suspended).

Not sure how this is happening, please can anyone explain?

Version (include the version you are using, if applicable):

25A.