Welcome,
Well done for winning your battle with cancer and for losing weight.
Although I am personally not too convinced about the long term sustainability of the Dukan diet,I thought I would try to find out the 'official' answer to your question since there are a lot more resources in French about this diet.
On the 'official' forums when someone is diabetic and asks about the diet the official response always is consult your doctor so it's perhaps not surprising I found very little about diabetes and Dukan.
However I found a video of someone asking Dr Dukan about hypos on his diet. She isn't diabetic but she has suffered from hypoglycemia.
http://www.dailymotion.com/video/xbvdb8 ... _lifestyle
First he gives the treatment for hypos with symptoms when glucose falls below around 3.7mmol/l (if you listen he mentions 66-65 which is using g/l as they do in France, they define hypos at a slightly lower level than in the UK ).He tells her that the correct treatment is to use rapid sugar.
(as a T1 I use dextrose tablets for hypos which each contain about 4g of carbs, the offical treatment is 15g of fast sugar but I often use less)
He then says to avoid the hypos she must make sure that she takes a soup spoon(tablespoon) of oat bran 3 times a day. She replies that she already does that in the form of galettes.(oat bran pancakes) He then suggest she consults her doctor which she says she has already done and is healthy (so presumably not diabetic). His advice is then not use the attack phase and to go onto the cruise phase. He asks if she moves, exercises too much. Her job involves walking, he tells her to eat well, not to deprive herself of food and to make sure she eats enough protein foods for breakfast. He suggests that this is an unusual problem.
She then asks about using cornflour and how much to use. He says that you can use a tablespoon per day in the recipe for galettes (I wasn't sure if this was in the context of hypos,but I do know that one method used to avoid hypos used sometimes is to use cornflour in snacks, )
I found that there is a Dukan UK forum, you could also ask the same question there.