I applied the workaround stated here Network device in not present - #17 by kenjiuno
the only way to fix this issue on the current netifd codebase is to restart the network service by service netword restart... it isn't the ideal solution to me as this messes up the dynamic interfaces like wireguard and veth docker interfaces, idk how to restore it after the network service restart? restart docker daemon service? restart wireguard? might as well reboot the entire system
although the problem in the reference thread was DS-LITE, this applies to PPPoE DHCPv6 PD as well...