They have discretion to issue a licence before the 5 years is up, I think it’s about 8 weeks, but that only means you have the decision before the due date, you can’t really do anything else with it.
They have said mine will be returned on Feb 3rd but they didn’t half make a right pigs ear of getting to that decision so I’ll believe it when I see it.
I had a medical (you know, the one where a doc you’ve never met ticks boxes depending on what you tell them and then helps themself to £50) and I filled in a D2 which you can get from the Post Office.
I’ll need a DCPC but can’t apply for Mod 2 until then and no one will take a booking for Mod4 until I have Mod2 in my pocket so that going to be the thick end of a month.
By the by, have you read the report ‘Driven to Despair’ published by Parliamentary and Health Service Ombudsman?
You don’t say if you have complained to DVLA and/or DMG but this report is pretty damning and your circumstances may be similar.
Good luck