My ipv6 connectivity is working fine and I can see that I'm getting a /56 from my ISP with pcap.
But since upgrading to 24.1 I don't see the prefix listed for the wan interface under Interfaces > Overview.
Is anyone else having this issue / is there something I can do to fix it?
Yes, this essential information unfortunately seems to have been removed:
https://forum.opnsense.org/index.php?topic=38223.0