Hi airmail,
I've had my PPL for nearly three years with a class 2 medical. I've had diabetes since I was 10, I'm now 26. The CAA have an excellent team of professionals onboard that deal with the diabetic medicals. They really are leading and pushing to get EASA onboard.
There is a lot of evidence to produce, but I agree with all of it. We have to be precise and stringent about it. Good evidence and honestly will prove to EASA that diabetes is not a problem when it comes to taken control of an aircraft.
I myself am currently going through some changes with my regime. I declared myself unfit back in February because I came off of the pens and have since started with the pump. Luckily, I am in the middle of my IMC training, so I am still doing lessons with my instructor and building up evidence. I wish I'd been on the pump years ago to be honest. So much better control.
I wouldn't say it's challenging. It can be time consuming and there are a lot of points to cross, but the team at the CAA are good and they know their stuff.
All the best!