If you've just been promoted it shouldn't change down again for months. I often do slow recovery rides and it doesn't penalise me.I have but not for a long time.
Perhaps I need to update it.
I'll give that a go at some point.
It also did it on my last ride but got promoted instead,so it constantly adjusts.
If you do get dropped down again today it could be worth checking your settings and/or contacting bkool.