172.31.254.0/24 range is for manual assignments and 172.31.255.0/24 range is given out by DHCP. I do not need that many IPs, it’s just for convenience.

I do similar for my home network, mostly for a combination of future proofing and ease of use.

Realistically it would probably make more sense to segment it with more networks, but I'm only going to go so far with complexity for my home production