Alternatively, you may consider doing the FAA PPL while over there anyway.
Benefits: saves money (CAA fees, no night qualification needed as included), you can continue hour building immediately.
The UK JAA PPL is usually done more for sentimental reasons, as you will loose it up on gaining your CPL, the FAA PPL is yours for life.
Alternatively, if still possible, change the state of licence issue of your JAA PPL, some countries send your PPL by return mail with a courier...