It is enough to update it once or twice a week, because then there is usually a solution for any errors that appear afterwards. It is perfectly suitable for daily use.
Others already answered your question, but I thought I’d add:
It sounds like your use case needs a “just works” OS/distro.
While I love Arch and Arch derivatives, this choice may potentially™ prove to be troublesome in the future, given your concern of available time to deal with your system (Arch and its derivatives often do need some intervention/maintenance).
If you go with bare metal installation and use EOS as you main OS where you do all your work/homework, I suggest you make sure to at least take advantage of BTRFS and snapshot capabilities for your peace of mind.
Normally, sudo pacman -Syu is enough to update the system.
-y, --refresh
Download a fresh copy of the master package database from the server(s) defined in pacman.conf(5). This should typically be used each time you use --sysupgrade or -u. Passing two --refresh or -y flags will force a refresh
of all package databases, even if they appear to be up-to-date.
Once a week is generally considered often enough. On my daily driver I updated as often as my task icon tells me there are updates. But on my other machines it’s usually weekly and occasionally monthly. Although when it’s been monthly I do occasionally have to update the keys first before doing updates.
As has been mentioned try btrfs with snapshots, I’ve not hade to use them yet, but I like knowing they are there. And before assignments, avoid updates as it could be a rabbit hole you don’t have time for, better to skip a week or two than let stress and time pressure break your system.
Weekly is a good plan - but the difficulties it causes are generally exaggerated. I have been running EnOS for a couple of years, and the total time for update ‘tweaks’ doesn’t amount to 10 minutes over that span of time. Most of that was an XFCE update looking strange on my video card when I first started using EnOS - and that was worked around in 2 minutes, and solved by a later update soon after.
I actually find it MORE reliable for daily use than Ubuntu used to be, though the difference is small. Certainly the updates are more frequent, but FAR less of an ‘event’ - especially when 'buntu needed a version upgrade!
Yeah, rolling release is a pleasure, you don’t have to f** around with major upgrades and stuff. Makes daily usage so much easier. As long as it isn’t a critical environment, I would never use anything else except rolling release distros. And if you don’t tinker them to death, they are stable as hell. (At least this applies for Arch based and OpenSuse TW, my 2 cents.)
Some of my systems I use less frequently, I update about once a month. Never had any major issues. Of course, the longer you wait between updates, the higher the chance that the update will require a manual intervention.
Even if you update less frequently than that, there won’t be any issues with system stability because of that. Your system will not just break on its own even if you completely stop updating it. At some point, there won’t be any mirrors serving you old packages. Also updating after a very long time could be quite a chore.
But theoretically, you could have an offline computer running Arch Linux which you never update, and never install anything new on it, and it will run perfectly indefinitely.
A much bigger issue with updating less frequently is not getting any security fixes. There are critical vulnerabilities in your browser just waiting to be discovered and abused, so you want to get those updates as soon as possible. This is true for fixed release distros just as much as it is true for rolling release distros, the difference here is that you always use the latest version of all packages after you update. There is no separation between feature updates and security updates.
So my advice is: update whenever you have the time to do the update, and fix eventual issues that seldom arise from updating. Pick the most convenient time. Don’t update your work computer hours before an important deadline, but also don’t wait too long between updates so that you run software with known security vulnerabilities.