I was at SFB for 5 years before gping to ATL, however my ATM (At the time) would have let me go after a year of CPC as we were well staffed. And of course, I had been an FAA controller at several facilities for 19 years before getting selected at ATL.
And no, as for the paperwork it was simple. From the day I submitted until I was selected was about 4 months, then 2 months later I was moving.