Hi, well what you should really be aiming for is to stop eating sugary foods, ie. biscuits, also weetabix is not ideal as it’s very carb heavy, carbs are sugar by a different name.
On saying that, the numbers look pretty good so I assume his insulin resistance may not be too bad, this is good news as it means your diagnosis could be used as a warning and opportunity to stop things before they progress.
You are aiming to keep numbers around 4.5 without food, no more that 2 points over your before food reading- two hours after food.
This is my uneducated opinion, based purely on my experience and research from the internet, my wife has set a helpful president of ignoring everything I say. this is assuming he does not take insulin or other blood lowering meds (except metformin). If other drugs are taken, the numbers change due to hypo risk.
Best of luck, keep reading.