Yes. At any US airline I know of, you cannot arbitrarily bump a junior person out of seat/equipment/base any time you want just because you're senior. Not fair to someone who moves to base, buys a house, establishes wife and kids in job/schools, etc.

If you get bumped, either by company reductions or a senior pilot, then you can bump anyone anywhere if they're junior to you.

If you really want something, better grab it at the first available opening... otherwise there may not be another opening for a while, possibly a long while.