Not necessarily, they could actually want a LB at 12 and take Rudolph/Jackson later. Theoretically the cost could be too high for what the Bills are comfortable giving up or they simply may actually like Rudolph/Jackson better. They will have disgruntled customers if they don't trade up and have some if they do. Could always run some damage control by saying we are trying like hell to move up, if it doesn't happen at least it is out there that they tried and it becomes presumed that we just couldn't get a deal done because no one wanted to drop back that far or were stuck on a player. This would be evident by staying put and they will be able to do the usual lip service that we got the exact players we wanted, best in the draft, highest on our board yadda yadda yadda...As we know they won't say yeah we tried to trade up and it didn't happen so we took these other guys instead....
I don't really believe this is the case, but it *could be* a way to tamper the expectations from the fan base who are clamoring for them to go get a QB. Tin-foil hat thinking is where I was going with this btw.