I observed that my Shelly Plus 1PM and 2PM devices remain discoverable via the Shelly app, after I turned them into Bluetooth proxies in Home Assistant. I have to admit that I expected that these Shelly devices would stop being discoverable after configuring them.
Also, to turn discoverability off completely it seems that you need to disable Bluetooth scanning in Home Assistant - if you only turn off Bluetooth off in the device’s web UI, it seems that the Home Assistant integration turns Bluetooth back on again after the device reboots.
Unless someone could tell me if there is a way to use Shelly Plus devices as Bluetooth proxies without having them discoverable via Bluetooth in the Shelly app?