Ah - no one told you that the problem is the carbohydrates?
At least your Hba1c was not all that high, so as long as you are eating fewer carbohydrates than before it should show improvement.
Personally, I wanted normal numbers and I was starting from Hba1c of 91 and a lamentably high carb low fat diet intended to lower cholesterol.
I don't eat grains, nor starchy veges, but I do eat meat with fat, also fish, seafood, cheese, full fat yoghurt, only low carb fruits such as berries, also eaten with cream. I used a meter to test my blood glucose and reduced it down to 8mmol/l after eating. I then stuck to the same foods and saw the levels continue to drop eventually I saw under 6mmol/l after eating Christmas dinner, so I knew that I had it beaten if I kept to the diet.
We all react differently to foods, so without knowing what your blood glucose might be then it would be impossible to put a figure on it - and the readings I get would suggest a Hba1c in the 30s but it is stubbornly at 42 - so it isn't an exact science in the first place.
However - not having a meter is rather like not having a speedometer in the car - only when the fines started to roll in would you find out you are a poor guesser.