What does "adopt" do to existing ESP32s?

I set up a couple ESP32s to be Bluetooth proxies using this page. I recently installed ESPHome and saw the option to “adopt” them. I only tried with one, but after doing so, it no longer sent iBeacon info to Home Assistant.

I’m new to ESPHome - what does “adopting” do?

Tried again this morning and everything worked as expected. I must’ve renamed the proxy on the first try…