There is a fundamental difference now:
AND your speeds exceeds the speed of the bike in front of you
This part was not working well before, causing a lot of weird behaviours. That effect you reported shouldn’t be the happening this time, and if it is, we need to go back to the drawing board.
My draft is higher because I’m still in the group of riders stringing out the back.
Besides, when you are in single file, it’s difficult to reach the necessary draft thresholds. You need to be in a more tight group.