Comment by sgjohnson

If you have a /48 assigned, you’ll burn the prefix in your brain. Leaves 16 bits for the network address.

e.g. you’ll get 2a06:a003:1234::/48 from the ISP - what you’ll really need to remember is the 2a06:a003:1234:xxxx::/64 part. And I use the VLAN id for the xxxx part. Trivial.