I have had it happen. Sudden remission. I call them my honeymoons. During my last one, just a couple weeks ago I gave myself an OGTT to test whethe I was glucose intolerant and amazingly I was not longer at diabetic levels (https://forum.tudiabetes.org/topics/human-self-experimentation).
That being said, my theory is that once your pooped out pancreas has a chance to catch up with things, you start “storing” insulin for a phase 2 response. You always had high blood sugar, your body nevery had a chance to store up insulin. Now you can and your phase 1 response allows you to eat “some” carbs and respond normally.
My suggestion, enjoy your newfound health, but still eat low carb. Treat yourself, but don’t overdo it our you may poop out that poor phase 1 response.