When on TRT its every 6 weeks till you get stable. Once stable then you goto every 12 weeks then 24 weeks.
If you are coming off TRT then you need to be monitored for a close every 4 weeks for a few months along adrenals and thyroid.
TRT once it will be for life. The thing I see alot is that alot of guys do not need to be on it in the first place.