To be honest I think the fact it's called a 'honeymoon' is a bit misleading - it makes it sound wonderful. In fact it can be a bit of a nightmare, as you've found, because for some of us the pancreas doesn't restart again properly; it just works in fits and starts. Mine didn't pack up properly for ages - was working fine, conking out, working a bit, conking out, etc for about 9 months. I think it sometimes pumped out a bit of insulin, just not quite enough, and sometimes whacked out too much, and it was hard to predict. There's not much to be done about it apart from what you are doing, keeping an eye and trying to make sure that the highs don't stay too high for too long.
I wouldn't worry too much about the occasional high. It's very, very hard to get bloods 'perfect' when you have type 1. Don't beat yourself up about it.