Insulin and T2's-is it permanent?

I've been trying. I think it rather depends on how much insulin you're producing and how much insulin resistance you have. I have managed to stop using my bolus insulin and have reduced my basal to just 10 units a day. When I cut it out altogether my levels were too high, even when low carbing at around 50g per day.

I'm now waiting for the results of a c-peptide test to see if I still have any insulin production.

I would say it is possible - especially if you've had insulin resistance and the diet improves this. But it won't work for everyone.

Not necessarily, there are several I know of
It depends on the individual, lots of varieties of diabetes!
Sid Bonkers did it.

FergusCrawford did it too