PPL exams you can def get before heading to the US to do the flying, I know people that did this, all you need is the proof as its the CAA that issue the license not the US school and they check the lot out.
2nd question, are we talking about the ATPL exams??
does anyone know if you need a PPL license to sit these or can you just do them? some schools say you must have 150hrs first, but thats only so you can carry on with IR straight after so not a CAA requirement!