The situation as follows.
You have held an MEP and now it has lapsed.
The rule would be the same. They can't issue you an MEP IR unless your MEP is current. (of course no need to do written exam, just a revalidation required)
Once you have both then you can let them lapse.
If the MEP lapses and you want an MEP IR then you must get your MEP done.
This can be done on the same flight as far as Mr. Green knows (examiner I spoke to regarding own circumstance).
This is how they work.
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