I think the concern was over how open ended it would be.  The swap is done by sending your PRT to a special PRT exodus address.  A script then sends PRTX back to your PRTX address.  Have to write up all the details, but essentially your address stays the same, you export/import your private key from old to new and we run a bot that does the swap.  On the one hand having a deadline would make sure unclaimed coins aren't just sitting out there forever, on the other it is an issue for folks who are long term holding and don't check up on news or run the wallet very often so they might miss a broadcast message.  The Exodus addresses will be public and trackable so I don't think we have to worry about unclaimed coins disappearing into the ether.  I think we will be able to do this pretty smoothly.