Hey UA,
Good to see you back again.
From what I understand of the exam valididty, the only way to secure your exam passes is to do the IR first. That would then secure your exam passes for 7 years (assuming you do no more renewals in that 7 year period - every renewal extends the ATPL exam validity for a further 7 years).
I am not sure what the rules are on adding an Instructor rating to your PPL would be, but would that be a possibility? It would keep you flying, but you may not be able to earn any money from instructing.
Drop me a PM if you are bored at work for a chat.