No and no, Clive. Simply learning as I go. I might end up Type 2 eventually so am thinking ahead.
I do not know anything about medically restricted licenses so am wondering who they might apply to and how it might affect me.
Googling, I see retinopathy and neuropathy is a reason given for restriction, so that could apply to me eventually.
I am also very interested in the Libre device.
Does that answer your question @evilclive ?
If you're diagnosed T1, you lose your licence and have to reapply. When you get it back it only lasts 1 or 3 years. There are also rather more stringent restrictions on driving lorries and busses. Some T2s might need to apply too, though I suspect that wouldn't apply to you for a fair while. https://www.gov.uk/diabetes-driving has details.
For diabetics they're mostly concerned about hypos. Losing eyesight (eg by retinopathy) is covered under a different part - the standard visual acuity to drive, which applies to everybody. Again, with the HbA1c levels you mention, this seems unlikely to be a problem for you for a long time.
Re libre - yes, I think it might be intersting to try one for a couple of weeks in your situation, though probably not worth using full time unless you're really keen and have the cash. Do you have an NFC-enabled phone? If so, you just need to find a sensor from somewhere - as you've found, they won't sell direct to you for a while while they work out their manufacturing capacity. Maybe try Asda or Superdrug pharamcies?