@Tannith
There are many examples on here of people getting type 2 under control, i.e. non diabetic readings through a combination of any of LCHF diet, intermittent fasting, and low calorie diets . Many T2 diabetics ( though by no means all ) are overweight to varying degrees. Look at the testimonial section.
It seems to be reasonably consistent that many newly diagnosed diabetics can improve their situation quickly even to the non diabetic readings level by following the low carb advice on here.
Based on the research outlined in this paper ( which is only tentative at this stage) - I see the implications being :
How quickly hba1C improves could be a function of how overweight you are , how high your hba1C is and how quickly you lose weight by whatever means.
My reading of this research and the various comments made on the forum read me to think that the following may hold reasonably true for many T2 individuals.
If you are not very overweight but your hab1C is very high, then the hba1C should start coming down very quickly without needing to lose too much weight as long as you reduce the carbs. - this may mean that those already in the normal BMI range can achieve non diabetic readings simply by reducing carb content but keeping weight stable or losing only a few pounds of what is effectively visceral fat - ( TOFI)
If you are very overweight and have a high hba1C then you will need to lose quite a lot of weight to get the figures down but it should start to come down quickly alongside the weight loss
If you are very overweight and have a Hba1C that is only a bit elevated, then it may be that it will take a long time and a lot of effort to get your numbers in range - and that may be because you are not actually that insulin resistant in the first place - instead you may be more in the nature of a metabolically healthy obese person. (google the concept)
From my own readings of this forum it seems that for many of us ( including me) the first stage of the process works quite well - ie we can lose 3- 5 stone and get our numbers into a reasonable range - i.e. around pre-diabetic numbers. - after that it gets much harder to both lose additional weight and improve hba1C further - this may be because at that point we are becoming more like the category of metabolically healthy but obese people.
All of this is just conjecture on my part, so no doubt others will have different opinions.
Suffice to say, whatever your precise situation, eating only real food , eliminating most carbs and losing weight will all move you in the right direction !