Maybe I’m misunderstanding you, but that’s not quite true. it’s the second bid month after the activation date, which is pretty confusing. So, if your effective date per the vacancy bid is 5/1 say, you start receiving the extra pay in the July bid month.

Search for “activation” in the UPA and you’ll get a bunch of examples of different types, dates, and bump/downgrade info. I started out bummed when I realized I wasn’t going to get left seat pay for right seat premium pay trips after my “effective date,” but quickly realized how many people had to read this as they were being constantly bumped back in the lost decade