Another good blog here written by Dr. Peter Attia, a very knowledgeable and interesting guy:
The Eating Academy | Peter Attia, M.D.
I had all kinds of weird ups and downs the first week I was on the diet. I would get up in the morning and my blood sugar would be 130-150, but then would gradually come down as the day went on. Just like you, I think it was a case of my liver releasing glycogen stores while I slept.
The other time I had trouble keeping it under control was around Thanksgiving. It totally perplexed me, because I thought I was being good. What I suspect happened is that I was exceeding my protein limits by scarfing down leftover turkey and ham. As I'm sure you are aware, any excess protein that the body can't use is converted to glucose. Just as if I had eaten a pastry. I've adjusted my eating to cut back on protein, and voila! Blood glucose was back to normal within a day.
My fasting BG is almost always right around 92-94 when I get up in the morning. By midday it's usually down in the mid to low 80s. After I eat a meal, it may go up 10-15 mg/dl but comes back down within an hour.
Interestingly, my wife's BG is typically a little higher than mine. She's on the diet, too, but is not diabetic (her last A1C was 5.3). She's lost about 12 pounds, last I heard, and is looking good.
By the way, I've now lost 34 pounds. And I'm actually looking forward to getting my blood work done again in January.