Stop panicking.
Just an example:
World of Warcraft has 12million players where continuous internet connection is required to play the game. Every Tuesday the servers go down for maintenance lasting usually 8-10 hrs some Tuesdays they have a reboot maintenance where the servers are down for no more than 15 min. Recently the Tichcondrius realm was down for two days straight. That's the longest ive experienced in a lock down. I went and did something else till they got the realm back up.
Ubisoft SH5 servers crash or go down for maintenance. So what?
I would rather Ubisoft have a maintenance day like WoW and shut down servers once a fortnight or month so they can make our online experience always up to par. I mean your not going to play the game 7 days a week 24hrs per day are yas? well some might attempt it
Your save games will always be available when you log in (SH3 save game bug), your character profile will never be lost even if you delete it or your hdd spits the dummy and corrupts your game - no worries your files will (should) be available to grab of the server.
There are some good points of having online connection to play games.