Although A319/320/321 have a common type, the 321 is in a higher pay group than the 319/320, the same group as the 757. And the A321 isn't listed at all in 8-D-1c .

I realize there aren't currently just a lot of 321s in the inventory, but are the 321s managed as a different vacancy group flown by a subset of the 320 qualified pilots who fly nothing else, or in common with the other 320 qualified pilots but just receiving the higher pay schedule when happening to actually be scheduled to fly the 321? For that matter, if someone is a newly minted 737 pilot, can they break seat lock by going to the 321 since it is in a higher pay band? If that's anywhere in UPA 23 I haven't been able to find it.

Thanks