Well i can say with confidence that if you did stop that, youd lose a lot of size.
I had the same situation now before i came off fully, very low dose test, of course there was some glycogen loss but strength etc still stayed the same or was still rising up, at test dosages that put me in the natty range.
Im a firm believer that no matter what dosage of test u do, even if it puts you into normal ranges, you wont be catabolic and wont burn off most of what u put on during blasts.
Get off and even at high natural test levels, you will lose alot.
Thats what sucks.
I would do trt indefenitely if i wasnt still young and if i wasnt scared/annoyed of constantly having to find test sources and shit because here trt is a nono