Companies jr man upgrade from the top down. It’s the only clean way to do it. Can’t effectively scatter upgrade off the bottom (senior FOs will say you can).
Its also the best business decision. Force upgrade the most qualified- not the least qualified. Which tells you exactly how it will occur.
There were only 30 some upgrades per month since March. The other shoe was always going to drop in the fall with that small a number upgrading. Senior FOs get to sleep in the bed they made.
Edit- I didn’t come up with this on my own. At May CQ the training dept told us how forced upgrades were going to shake out “this fall”. If you’re a senior FO you failed to read the writing on the wall. Some senior FOs did OBTW.