Hi and welcome from me too.
Sounds like you have only just strayed over the border into a diabetes diagnosis, so some simple changes should soon have you back where you belong. I would imagine your HbA1c is likely high 40s-low/mid 50s from what your doctor has said and good that they are giving you an opportunity to sort it out without medication first, so lots of positives there.
From what you say, it seems like you started the Exante diet just before your diagnosis.... or am I reading that wrong.
The Exante shakes were I believe used on the original Newcastle diet, which was designed to try to reverse Type 2 through rapid weight loss, so they should be fine for you to continue.
Basically there are 2 main schools of thought....
A very low CALORIE rapid weight loss diet (such as the Exante shakes provide) to reverse the fatty deposits, particularly visceral ones around the liver and pancreas which cause Type 2 ....
OR
A low CARBOHYDRATE approach where you reduce the amount of glucose going into your blood stream by reducing the carbs you eat, thereby allowing your body to cope. This is seen more as a long term control of the situation because whilst many people can and do get their levels back into the normal range like this, they do usually still need to watch their carbohydrate intake to a greater or lesser extent, so it is a lifelong change in the way you eat. It can be just as enjoyable once you get your head around it and find low carb treats that you like and it does gradually become a way of life and you don't crave the high carb foods anymore. Anyway, you are basically managing your diabetes by choosing lower carb foods.
The very low CALORIE diet with the shakes is looking to reverse the Type 2 via weight loss but you have to maintain the weight loss to prevent the diabetes returning. For me, as a previous YoYo dieter, therein lies the problem, in that once I start eating carb rich foods, I want more and more and I put the weight back on. Eating low carb has given me the control over my eating that I have struggled with for decades, so this way of eating suits me.
Some people do a combination of both approaches and count CALORIES and CARBS, but for me that is a little more complicated and I like to keep things simple.
I will admit that learning to eat low carb was really difficult at first because culturally we have been piling our plates with carbs to fill us up, pretty much all our lives, so it was pretty mind boggling contemplating life without bread and spuds etc (bread particularly is a carrier for so many foods) and of course some people don't need to do without these altogether but just reduce the portion size and frequency of eating them. For me, now, most of the time I just don't want of need them, but every once in a while I will have a small portion. They are not off the menu completely but I know that to maintain "control" over my cravings, I need to be wary of them.....
You however may be very different to me and losing weight and maintaining that loss may be the easiest option and of course, you can always try one approach and if it doesn't work for you, you can try another option. Diabetes is very individual and being successful at managing it is about finding what works for you as an individual.
Best of luck and do feel free to ask any questions. I have every confidence that you will be looking at a reduced HbA1c result at your next test.... assuming you don't overindulge too much over the festive season... The odd treat is totally acceptable, particularly on the day itself. Good luck.