Originally Posted by Nitefrater

Of course you're hosed. What would ever lead you to imagine otherwise? Once you block out on a trip, the only limitation that company has on extending you is age 65 or your willingness to call in sick.

As far as pay, if you were pay protected for the original 12 day trip, (and you should have been) then the pay will likely stay the same. The extra pay provisions generally apply to the difference between "originally scheduled" and "as flown". Sounds like those two will now match up.

But I could be wrong about all that, and contract admin will give you the authoritative answers you don't want to hear.