1: https://xmpp.org/extensions/xep-0375.html 2: https://wiki.debian.org/UnattendedUpgrades
If you want alternatives there is jabber.at, which has also proven to be very well maintained in the past.
And there is jabber.de (but they don't have MAM (yet))
When it goes down, it goes down for multiple days, even a week. Prolonged outages have happened twice or thrice in the last two years, with no helpful messages from the staff. Heck, they didn't even bother announcing the outage before I posted on their community forums.
Their server stopped pushing offline messages to clients a long time ago. People complained, it still doesn't work on my end.
They said they would look into creating a status page, but we still can't tell during an outage if they know about it or not.
The bottom line is that maintaining their XMPP server is simply not a priority for them.
You should look into other providers that use better servers, and are also interested in maintaining their node.
EDIT: I'm basically asking you people to recommend a better XMPP node, somewhere you've personally had a good experience over a long period of time.
While nowadays most of my contacts are on private XMPP servers, I remember few having some reasonably solid experiences with https://jabber.at/ (can be also found at https://xmpp.zone/ for a better sounding domain name, which I guess matters to people who hate the now obsolete "Jabber" term). Can't from my personal experience vouch for a "good for a long period of time", but if someone is looking for at least a well established server, this should be as good start as any. Also, the news page shows they're quite serious about server updates and transparent, which is a big thumb up in my eyes.
Edit: typos