Quix, I'm reasonably certain that left-behinders who get saved during the tribulation will be changed into an immortal body upon Christ's Armageddon return; can't remember the specific reference, but I'm pretty sure I've read it.
MM
I can't recall a single Scripture that would remotely clearly indicate that.
It COULD sort of conceivably be. But I'm very skeptical.
For one, there will be children born during that thousand year reign.
Now, if Armageddon is at the end of the thousand year reign . . . I don't know. Not much said about the therefore then what's.