Pet traveling unaccompanied

Due to my oversight, my cat is only one month into his 6 month waiting period, but I am moving in December.  He won't be finished with the waiting period until March 1.  In the meantime, he is staying with a friend.  Does anyone have any experience bringing your pets into the UK after you have arrived?  Are there any pet transport services that are recommended?  Any other advice on getting my cat safely over?  I am moving to Scotland, and I'm pretty sure he will have to fly into Heathrow.  Thanks!

I used a pet courier.  My story is here.  I would highly recomend that company if you're on the east coast.  They arranged everything including the vet visit for the pre-flight certificates/treatments.  A bit costly, but worth it.  Someone else might have advice about couriers from other parts of the US.

ETA:  You might not need a shipper at all if you are sure his or her paperwork will be taken care of and an airline that flies unaccompanied pets is near where your animal is.  We didn't want to risk the people who were caring for him messing up his paperwork and the two leg flight would have been difficult at best (impossible at worst).