My understanding is that the holder of a UK licence csn still take the CAA route to the IR.
Specifically this means that they can sit the UK examinations, provided these are passed by November 2001.
UK licence holders are also exempted from the requirement for an approved IR training course (as required for JAR FCL) provided they meet the experience requirements which are summarised in CAA general information document 15.
Effectively the route to an IR for a CAA licence holder is unchanged, provided the theory exams are passed by November 2001 and the experience / test requirements met so that a licence can be issued by 30th June 2002.
Links below are to August 1 licensing policy update and the relevant General Information Document.
General Information document re: IR
CAA August licensing update