Switching GC / picking different one from before

[Alhanelem]

I'm well aware you can't wear the gear of a different company. That's not iin any way what I'm asking about.

Again: If I choose a different company initially from the quest (not the one I was in for 1.0), do I lose my rank forever, or will I have it again if I join that company at a later time?

Information seems scare b/c we couldn't switch in beta 3...