My /24 came from ARIN's NRPM 4.10 block [1]. Basically, you can get a /24 if you'll use it to help IPv6 adoption, which is what I'm doing: my web hosting service will offer shared IPv4 and dedicated IPv6 (like Fly.io does), and same for the ISP - CGNAT for the IPv4, dedicated IPv6 subnets.
My /24 came from ARIN's NRPM 4.10 block [1]. Basically, you can get a /24 if you'll use it to help IPv6 adoption, which is what I'm doing: my web hosting service will offer shared IPv4 and dedicated IPv6 (like Fly.io does), and same for the ISP - CGNAT for the IPv4, dedicated IPv6 subnets.
[1] https://www.arin.net/participate/policy/nrpm/#4-10-dedicated...