Sir,
It sounds as though you reside in the UK.
I can only speak from what I know in South Africa-here we do not recognise an IMC rating, it is IR or nothing
I woul'd strongly reccomend that you go for the full blown IR, maybe a lot more work but it sounds as though you woul'd like to carry on and go commercial. If this is the case-the only way is full IR and then multi with IR (there is a difference!)
Regardless-Good Luck and I hope it all works for you.