I gave up using the Libre gadget two years ago, because it gave costant spurious bg readings, especially hypo alarms, which were completely wrong. It is outrageous the way this thing is still being marketed.
I have found the so called diabetes nurses absolutely useless. They have a very mechnical approach to management of diabetes and seem to be utterly ignorant of the real issues, even worse than the GPs.
I was appalled by the inaccuracy of the original Libre and eventually gave it up. I would not go for a newer version unless I could be shown it really was worth it.
Speaking form experince, porridge is a big NO NO as far as BG goes. Blueberries on the other hand, no problem. Bananas not good. By the way I do miss my daily porridge and banana, so need quite a bit of discipline.