u/Independent-Mess5857

I just purchased a TCL 50 Pro (2024) and I have not turned it on yet.

I specifically need to keep the original Android version that the phone ships with and prevent it from ever upgrading to Android 16. I’m concerned that the phone might automatically download or install the update during the initial setup, after connecting to Wi-Fi.

For personal testing purposes, I need to keep the original firmware/version permanently, with automatic system updates completely disabled.

What is the easiest and most effective way to achieve this, ideally at the system level?

I’d especially like to know what I should do before connecting the phone to the internet for the first time so that Android 16 cannot be installed accidentally.

Thanks in advance.