Originally Posted by
DernierVirage
The fast track system is only available if you are in the UK. I have seen various agencies claiming that they can handle a fast track application on your behalf, thereby avoiding the necessity for you to go back to the UK, but I have no idea how trustworthy or reliable any of them are.
AFAIK, the fast track services require you to present yourself at a passport office in the UK. You can then get the new passport posted to you (usually takes 3 working days) or collect it the same afternoon.