Type 2 Hbac1

Blood pressure is not directly related to blood sugar - for a start I had many many years where my HBa1c was considered high, yet I've always had slightly low blood pressure.
I think some have found that blood pressure does get better if you're controlling your diabetes - but its not directly related to blood sugar - it's probably more that your body is happier when your blood sugar is at a good level - note: I'm speculating here

A low carbohydrate anti inflammatory diet can certainly reduce blood pressure and blood glucose, but I think HbA1c is more of a surrogate marker. My understanding of hypertension is that it’s part of metabolic syndrome just like diabetes. Confounding factors.

I believe the primary mechanism is thought to be narrowing of the arteries necessitating that the heart beats harder in order to move the blood around your body. Narrowing of the arteries will be alleviated by the same diet that alleviates high blood glucose.

Weight loss also seems to help enormously or it did in my case.