Diabetes and weight

Hi everyone. I was Dx (type1-LADA) in August of 2016 when hospitalized with DKA. My GAD antibodies came positive and A1C was at 8.7. For 6 months after Dx it was near impossible to get BG under control even when on both Lantus (70u) and Humalog (sliding scale) and my A1C went to 11.5. During that time I lost 70 lbs. Changed endo, got an EXCELLENT diabetes educator and went on I:C ratio for humalog and lowered the Lantus because of the decreased need due to weight loss. Added metformin (since I was apparently both type 1 AND insulin resistant) and came under control with an A1C of 6.7. After my sugar became controlled I not only immediately stopped losing weight, but have been gaining about 2-3lbs a month even though I am only eating between 60-100g of carbs a day and keep total calories 1200-1500. Obviously I rather gain weight than be blind/have neuropathy etc, but how common is it to gain due to sugar being under control? How hard will it be to try to control my weight now?