I don't think you can look at it that way.
The successful completion of the theoretical knowledge examinations will be valid:
for the issue of a commercial pilot licence, instrument rating (IR) or en route
instrument rating (EIR), for a period of 36 months
is pretty black and white, you have 36 months to get both a CPL and an IR. The CAA will not recognise these exams for issue of a CPL after 36 months, you will have to retake them in order to get a CPL issued.
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
It literally says it right in there, valid for the issue of an ATPL. You are not applying for an ATPL, not even close. These exams will not be valid for the issue of a CPL. The only reason a CPL isn't listed in the second set of requirements is that an EASA CPL is valid for life, so it doesn't factor in. You can let an IR expire, but still not lose the exams for 7 years, then eventually get your APTL. An ATPL and a CPL are very different things, you cannot use expired exams for issue of a CPL.