Def need more Sustanon (sust). Think about 500 mg Sustanon (sust) per week for maybe 14 weeks.
Your first three weeks u are taking combined 600-700 mg per week then dropping to 300 mg. if u consider your natural test is shutdown at that point 300 mg isn't much above testosterone replacement therapy (TRT) dosage leaving little for gains so Sustanon (sust) at 500 will yield better results to continue after prop drops off. And 10 weeks your body is just getting use to what gains have been made. 4 more weeks will give the body more time to gain and adjust to maintaining extra weight, making it easier to maintain is my understanding. Also add the aromasin or arimidex from beginning to control estradiol levels ffrom estrogen conversion. Also Human Chorionic Gonadotropin (HCG) about 500iu/week upto beginning pct to keep prevent testicular atropy and aid in faster endogenous recovery. Then pct with clomid/nolva starting about 2weeks after last test injection.
Along with eating clean and big. I know about weight loss from surgeries it sucks. Good luck.