I've had IPv6 up and running on my network for a while now, and I decided to enable it on my guest VLAN. I'm on Comcast, requesting a /60, so I added the guest VLAN to the dhcpv6-pd configuration on my WAN interface. No issues, the router has an IPv6 on both regular and guest VLAN interfaces, and my devices on the regular network have no issues with IPv6. Devices on the guest VLAN, however, are not getting IPv6 addresses. IPv4 connectivity still working as it always has.
I'm stumped.