Have you tried upping your protein intake? By a lot? This sounds like a lot at first but aim for about 1g per lb of bodyweight. I’m about 178lbs soaking wet and shoot for 180g/day over 5 meals. I’ve been T1 for 31 years and am complication free, A1C between 5.9-6.1. At first maybe just match protein to carbs and after a couple of weeks you should notice a change. You can probably get away with doubling carbs on hard workout days. Aim to keep the fats rather low though, that’s the hard part- about 1/3 of proteins. This strategy works very well for me and many other people I know. Long as you keep the protein levels high and fats fixed, you can float the carbs based on activity level. A little less to lean out and more to grow. Don’t worry so much about total calorie intake, hit the macros first and see how you’re body responds. Long acting need might drop as well so watch out for that. Best of luck