Knightsky is not correct.
Quoting from Lasors, section J:
A pass in the ATPL theoryh examinations will be accepted for the issue of a CPL or IR during the 36 months from the end of the month of the date of the final pass in the examinations. Provided that an IR is obtained during this period, a pass in the ATPL theoretical knowledge examinations will remain valid (for the purpose of ATPL issue) for a period of 7 years from the validity date of the most recent renewal IR entered in the CPL
(My emphasis.) In other words, once you've got your CPL/IR, the exams remain valid for ATPL issue indefinitely, so long as you keep your CPL/IR valid, or at least don't let it lapse by more than 7 years.
FFF
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