Hey Brother, good question. In bodybuilding, powerlifting and all things strength related, either with or without gear, everything goes in cycles. As you have seen in your lifting, you're never lifting your max every day/every week. You're building to it. And once you get there, if you're smart, you are backing off in the following weeks. We can only red line our training for so long before our CNS gets shot and we break something. We want to use gear to help us in these strength cycles. We build our lifts up as we cycle up in gear, but then after the cycle, we also want to taper our lifts back, or deload. 

I think that there are factors you can work on, to maintain your strength. First is, respect that your "super human" abilities are going to go down. Its just a fact and its a temp issue. Staying on HRT will help, but thats a whole conversation in itself. Do you want to be forced to rely on test for the rest of your life? Coming off, you will get weaker than on HRT, but you can maintain a lot of your strength through nutrition and smart training. So coming off, or going to HRT, you may need more food, more carbs and fats. If you keep the foods high, you're giving your muscle everything it needs to stay as strong as it can. The best you can do is create an optimal environment and then the chips will fall where they will. Eventually, you will hit a new baseline, and I'm certain that it will be at a higher strength than it was before. Then from there, when you cycle back up, you will be able to push even further than you did before. Its a game of 3 steps forward, 2 steps back...then 4 steps forward. We will have our ups and downs. Highs and lows. Don't try to fight them. Learn to accept them and ride the waves. Patience will take you very far