We have gone through the process of the PETS scheme and our dogs will be able to leave the US on July 12th. The problem is we may not be able to leave then due to the economy and my husband's job. How long will the process last past July12th before we have to do it all over again?
As long as you keep your dogs' vaccinations current, the intial rabies titer is good forever. The six month wait to enter the UK is the minimum time, but there's no maximum that I know of -- so long as vaccines don't lapse even for a day. Our cats vaccines were good for a year, so this was much more of an issue than folks who have the 3-year rabies vax.
Since you were slated to leave in July, I'm guessing you haven't done the certificate portion (or at least haven't sent it to USDA) of the process yet. But if you
had, the USDA endorsed certificate is good for 4 months from the date of endorsement.
I'm sorry you're facing a delay, but none of your efforts have been wasted.