Hi, great news about the improved glucose levels.
Do you take blood pressure tablets, and have you lost weight? Each Kg of weight is worth about 1 mmHg systolic BP so if you lose 10 Kg, your BP if on BP tablets may drop 10 mm Hg.
I guess that you have checked that you are not going hypo? Not an appropriate study, I know, but a study from Edinburgh looked at symptoms of hypo in elderly folk with T2DM on insulin, and they often reported being dizzy.
If it persists, I'd get checked out by GP to confirm BP level and any drop on standing (which can occur a few minutes after rising), and since you have T1DM, it might be worth considering Addison's disease.
best wishes