ShaniI have a device with an arch linux installed on it, which I haven't update for over a year. And now I'm to afraid to do it now. I probably going to reinstall the thing. Good thing is, that I have a backup of all the crucial config and data files.
Vile Lasagna@shawn the trick, from what I remember of my own experiences, is you may need to upgrade pacman-keyring first.
Be careful not to partial upgrade tho. I messed up and had to, like, find a standalone portable pacman to undo a booboo. But if you do the whole thing at once it should be survivable.
Another thing to watch for is that if you rewrite grub-config you may have to also reinstall grub to the efi. There was a breaking change,I think, at one point.... Not sure if within that time frame