This is not really a question because of a problem I cannot solve, but rather one because of a problem I did solve and am now asking myself why and how.
I essentially tried to get the Bluewin mail up and running on my machine but ran into a problem: the Email app just didn't want to connect to the server. I checked time and again that I had entered the right information into the form. As I became desperate I tried every single thing that came to my mind and in the end I got it to work, but not with port 456 on smtpauths.bluewin.ch but port 587 which seems to be the "default port for SMTP submission on the modern web."
So is the Swisscom support page simply wrong about which port is open for SMTP (which would be kinda embarassing IMO) or what happened here?