So I tried this feature out, went from a queue of 5000 for Phoenix to 50 for Twintania.
So far so good, I wanted to do MSQ anyway but later I decided I wanted to go back to Phoenix. I wasn't aware that not only did you have to do this while logged in, in a main starter city - Grid / Limsa/ Ul'dah - you could not leave the zone of the main Aetheryte. You cannot use your retainers. (This is just for people's information, I know alot of people know this) Also your position in the queue to return is either the same as people on free trial or possibly - after 4 hours I gave up - you are behind free trial users queued for your home server as well.
Worse than all this, I got disconnected, either from idling or some d/c and the queue into Twintania was now just as bad as getting to Phoenix. So finally after another 3-4 hours I am back where I started. In Limsa trying to return to Phoenix in a queue for idk how long unable to do anything. Don't go visiting unless you are fully aware you may be stuck there for a long time