Yes. Get the IR done or it's all 14 exams again (although I think they "graciously" allow you a credit for VFR comms for holding a CPL!).
Interestingly, Alex from BGS mentioned a couple of recent instances that if you do it the other way round (IR first), the ATPL credit remains valid for you to get your CPL after the 3yr period. Now seen this written in black/white anywhere though, and it's certainly not what LASORS says...