Honestly not too high and it could be that your body and liver especially are used to a higher number so it's trying to get you back up there. Took a fair few months for me to be seeing 5's and 4's in a morning. Your postprandial numbers are looking great and your outside of mealtime numbers look great as well so I wouldn't worry too much, like the lovely
@Rachox said it's the last number to come down and can be influenced by stress, sleep and so many other things.