I just got hit with that myself. Expected to get 179 (War Effort) then got told I would get 31 with the chance at more. The Friday before the order started the plug was pulled and now I'm scrambling for days just to make it until I get put back on the Delta payroll. Not at all upset about going back to Delta. Now that we've hired, I can actually move out of NYC/ATL MD88.
What I think will happen is that the budget will get approved and sometime next spring you'll see a lot of MLOA being taken again. If not, you're right, there will be a large number of folks (troughers/bums anyway) that jump back into a category. Couldn't tell you what that would do to seniority or hiring, Delta's big and there are not that many on MLOA.