The ATPL theory practically never expires - unless you quit flying helicopters for more than 7 years. See Part FCL.025:
(c) Validity period
(2) The completion of the airline transport pilot licence (ATPL) theoretical knowledge examinations will remain valid for the issue of an ATPL for a period of 7 years from the last validity date of:
(i) an IR entered in the licence; or
(ii) in the case of helicopters, a helicopter’s type rating entered in that licence.
Re the type rating, does an R22 count? Seriously, I may have missed it but it doesn't define what helicopter's type rating has to be entered on the licence to qualify for the validity period. If I am wrong, I apologise.