I changed my Plex email address several hours ago but I haven’t received the confirmation. I’m logged in for now but it’s not generating a new token which I need to setup some external apps.
If your email hosting service does support sub-adressing (i.e. emailname+suffix@domain.name), does it perhaps require you to explicitly enable it? And if so, did you do that before requesting the email change?
Proton Mail supports this. I use it all the time.