A few years ago there was a post on the forums, possibly by Dale Wisely, saying someone was redesigning the Generation head and that the Bflat was the first in line to go into production. Until now there was no sign of it actually happening. Maybe this is it?
I would need to see another photo to have a clearer idea what’s going on. It looks like the angle of your photo foreshortens the view of the ramp and makes the square end of the bump look wider than it actually is.
Every Bb Generation I have here (except pre-1980’s examples) has a straight front to the bump. Unless another view shows something different, I’m inclined to think what you’re looking at is nothing new.