I'm having IPv6 issue after upgrading from 23.05.4 to 23.05.5. Unable to get the /48 prefix. I had similar issue previously when using snapshot back in aug, I then got IPv6 working after switching to 23.05.4 and now the issue is back. Now I only got /64 global unicast without ipv6 prefix.
Edit: I set reqprefix to 48, after I restart wan6, I can see /48 for a second before it's gone.
Edit: ran tcpdump, router not receiving reply for dhcp6 solicit.
Edit: IPv6 is now working after switching off both router and modem for 10 minutes as suggested by this post to release some sort of MAC address lock.