This planned course of action by your doctor will lead to misery, your doc is mistaken because any amount of exogenous T will shut down your natural production.
You would have to stop TRT completely and let the exogenous T wash out of your system before your natural production will restart, but this will result in you returning to a low-T state.
I’m assuming you have been diagnosed with hypogonadism and therefore need TRT for life. I would actually recommend a slight dosage increase because your trough levels are a little on the low end. You could also increase trough levels by splitting up your dosage twice weekly if your T allowance doesn’t permit a dosage increase injecting weekly.
Run from this doc immediately and find someone well versed in TRT!
This belongs in “stupid things that doctors do and say” thread and is filled with stories like yours.