After giving it some more thought and considering it's looking like Zen 4 will need a new socket, that will mean these AM4 socket boards basically have no future upgrade potential, so might as well just get a proper cheap board. There might a Zen 3+ refresh later in 2021 but i'm sure that wont be worthwhile upgrade for anyone with a Ryzen 5xxx CPU.
So i was also looking at the Gigabyte B550 S2H that @
TheReflex mentioned because it's really cheap, or the
Gigabyte AMD B550M DS3H because it's almost the same price (~£90 but OCUK don't sell it) and both have Q-Flash Plus, so the BIOS can be updated without a CPU. The main difference with the DS3H is that it has 4 RAM slots and 2 NVMe slots instead of 2 and 1 respectively on the S2H.
The VRM's are pretty poor on both these cheap Gigabyte boards, and their heatsinks are far from great, but this is for a friend who just needs a 5600X and wont be doing any overclocking. Should be totally fine. Think i'll tell them to go for the DS3H.
but I'm afraid of the hassle to upgrade it
Don't be afraid, it's very easy.
Here's a video showing
exactly what you'll need to do. It's for a different Gigabyte board but the steps are identical.