As far as I've gathered, people who go home pick things up exactly where they left off - if we were all from the same dimension I'd say that time just flows differently here, but considering how many universes people are brought in from -- the only explanations I've come up with is existing outside of time, or people being sent back with their memories wiped before enough time has passed for there to be desernable physical changes. Honestly considering the Atroma's capabilities so far I wouldn't dismiss either.

[ he rubs his chin in concentration. ]

Do you know how it is accomplished? Theoretically? I know speed is one option, but it's a tricky one in closed quarters.