Atkins for Life was written by Dr Atkins. It has a few carb levels, topping out at 100. It was published Jan 2004 a few months after his death but the book has his own long-term maintenance plans and advice. I see it and the companion cookbook in thrift stores all the time, must have been popular as his "last book"
Sounds like you are doing fine so "Keep calm and Carry on".

Fasting has an even longer history for health...thousands of years around the world. Under my signature is one of Hippocrates quotes about using fasting to improve health. Fasting should be particularly useful to keep blood sugar in check.