Hey there! Welcome to the club, I had similar news recently - my GFR is currently 40 so will be on the waiting list for a kidney when it gets to 30 - "within 2 years" according to my specialist, but that's before dialysis is needed (at 15) so I'm pleased I won't have to endure that particular joy. I was considering pancreas alone anyway as I have zero hypo awareness and have had a horrendous 10 years or so, so I know a bit about it, here goes:
Pancreas transplants were not successful for many years simply because they are very complex organs and do much more than just produce insulin. The first transplants were complete replacements, and there was just so much to go wrong which often did. Now, although a complete organ is still "installed", the ducts which produce digestive enzymes are not fully "plumbed in", so your current pancreas will still be responsible for producing these. The new pancreas is there for blood sugar regulation only, any digestive enzymes it produces are cleared via an attachment to the large intestine I think.
You're better off getting the 2 organs at the same time, as the quality of organs is much higher - the average age of a kidney donor is 50, whereas for kidney/pancreas (which must come from one donor), the average age is 40 and they tend to be much healthier individuals.
The waiting list is much shorter, based on a blood type of A or O you could wait for a kidney for 3 years, but kidney/pancreas is 6-7 months. You're viewed as a much higher priority requiring 2 organs, even though one of those is elective. You'll be put on the waiting list way before you need dialysis, as this is not a treatment anyone wants to put you through, theory being you will be operated on just as dialysis would theoretically start.
Your new kidney should last much longer with the new pancreas, as it does not have to deal with the raised blood sugars that caused your original kidneys to fail. No more external insulin, no hypos, no hypers, a halt to the progression of any complications, no diabetes and only occasional blood glucose testing to make sure the new pancreas is producing insulin. DVLA still class you as having diabetes, because your transplant could reject which would put you back on MDI or pump therapy.
Here are the downsides: there's no getting away from it, it's a huge operation. Kidney transplants are almost routine in comparison. The operation for "The Double" is more like 6 hours than the 2 hours for kidney alone. The recovery time is also longer, expect to be in hospital for at least a month, whereas for a kidney alone you'd be out within weeks and probably back at work in a month. My nephrologist reckons on me being out of action for 4 months in total, and he also said I would feel a lot worse before feeling any better. Any surgery always carries a risk of death and this is slightly elevated over a single organ transplant, but not overtly so. Rates for post-op complications are also higher, but again not excessively. Anti-rejection therapy gets better all the time, with fewer side effects than even 10 years ago, but you'll still be taking immuno-suppressants for the rest of your life.
I don't know of many hospitals that actually do this operation, there are certainly none in the south west of England, so I will be done in Oxford. But it's definitely available in London and Manchester. We are a rarity!
It IS a shock to learn that you will need a kidney and on a timescale that seems much more real than it ever did before. While the option of adding a pancreas at the same time is a no-brainer for me, the positives far outweighing the negatives, it is a HUGE decision to make so I know exactly how you're feeling.
From the info in your post I may well be there before you, even though this isn't a race I'm terribly bothered about winning! But please feel free to PM me if you need to vent or share or whatever.
Good luck, Jo