Position update errors when the effective date is the same as a department effective date

Summary:

A department was updated with a new GL cost centre effective 1 July 2026, and when updating a position that uses that department effective 1 July 2026 with the new GL cost centre, the position update errors and doesn't go through. An example of the error is 'The value of the attribute Bargaining Unit Code isn't valid' which makes no sense because our start and end date for the bargaining unit codes are 01/01/1956 to 31/12/4712.

I found a workaround which is to update the position effective 1 July 2026 with an action reason, and then correct the department effective 1 July 2026 with the new cost centre. I'm not sure why i can't just update the position effective 1 July 2026 with the action reason and cost centre at the same time.