40mmol/l is normal, not prediabetic, not "at risk". Another graphic attached, showing the blood glucose ranges of non-diabetic people.
Secondly there is absolutely nothing magical about the 48 mmol/mol reading. It was agreed by the medics in around 2008 at the level at which they would all agree to "automatically diagnose" diabetes. The level was chosen because retinopathy is rare (not unknown) at levels below that figure. I had a nearly full set of diabetic symptoms awhile my BGs were around 43/44 mmol/mol, and despite the symptoms over ten years, was told I wasn't diabetic.
The issue for us is insulin resistance. If we have that, it stops the insulin clearing glucose out of the blood and into the cells as fuel. Instead glucose gets converted to bodyfat, or hangs around in the blood. High levels of blood glucose can do physical daamge to nerves and capillaries. It is likely, again in my opinion, that there may be several causes of insulin resistance.
Weight loss, if you have it to lose, is probably a good thing in itself. I'm assuming you lost weight through calorie restriction rather than carbohydrate restriction. Is that correct? My weightloss happened long after my BG was back to normal and was achieved by carbohydrate reduction, as I didn't limit or even count calorie intake. So (in my view) my carb reduction achieved two things which are linked but not necessarily dependent on each other.
However if you mauintained a relatively high carb intake while losing weight I can see why your BG might not be particularly affected.
My thinking is it's probably a good thing not to be diagnosed as diabetic. It affects things like life insurance, for example. And because there isn't a cure, you would never not be diabetic, not matter how well you controlled your glucose. I guess what I'm saying overall is that don't obsess about whether you are or aren't diabetic (the figures you report say you aren't), or whether you levels might or might not have been higher at some point in the past. The issue is maintaining normal BG levels now and in the future. You can do that fairly easily by only a relatively minor adjustment to your carb intake.