Yeah you can withdraw your paperwork up to the last day before the selection, but then let's say your release date is a year out. Then something happens between getting picked up and getting to your new facility. I don't think that's them shafting anyone, they're just between a rock and a hard place.
I'm just playing devil's advocate here, I would probably be on board with a policy to the effect of once you get a TOL you aren't eligible to put in ERR paperwork for x amount of time. I think that would incentivize people to only put in for places they actually want, and those that have to withdraw for whatever reason most likely aren't going to want to leave immediately anyways. I've also met some people that have controllers at their facility that get picked up, wash out, fast track back, get picked up, etc. This would potentially put in a buffer for those people to allow talented controllers that would certify to move up and successfully staff the system at the critical facilities.