It's more a case of how long you have to complete your exams is it not?
You have just 18 months from your first sitting to complete the lot...or it's back to the drawing board!
From completion of your exams you have 36 months to do your CPL and IR and whilst you could do your CPL before you complete the exams you cannot have any form of commercial license issued till you have a full set of passes.
An interesting gamble!! What happens if for some reason (God forbid) you cant get through the rest of your ground school or your CPL?? If I were you I would save the expensive bit till the end and benefit from the CPL training which will help loads when it comes to do your IR.
Anyway, whats wrong with Cranfield?....The amazing nightlife...the Pubs..the hive of activity....OK then... the empty tatty bars and the Kebab van! <img src="wink.gif" border="0">