Well the CAA may/must have changed their ruling on that or the FTO in the UK that I did my MEIR at were misinformed in my favour. I had been running under the assumption that my Canadian MEIR had to be valid before doing the conversion, but the message I was getting form the FTO was; 'No, so long as you've actually has an IR previously it doesn't matter'. So that was it - no full IR course for me but it did take me a bit more than the conversion minimums.
Good luck.
CG.