Cueeffee
I've recently done exactly that (BCPL JAR CPL conversion). I had to show the 5 hrs on a complex type which as it was so long ago in a long misplaced logbook I had to get an afidavit to swear I had the relevant hours, then I had to do a LPC in a complex type (LPC must be in the last 12 months so the CAA told me). Then it was a case of sending a big fat cheque to the CAA and the licence arrived a couple of weeks later. Oh yes and a current class one medical at the time of application.