> their router somehow lost the prefix route to me -- I was informed that their DHCP server adds router dynamically to routers for the curious, that's (in most

> their router somehow lost the prefix route to me -- I was informed that their DHCP server adds router dynamically to routers for the curious, that's (in most cases) DHCPv6-PD relay agent operation, https://www.rfc-editor.org/rfc/rfc8987.html#name-general https://www.rfc-editor.org/rfc/rfc8987.html#name-general "Delegating relay": Delegating relay: A delegating relay acts as an intermediate device, forwarding DHCPv6 messages containing IA_PD and IAPREFIX options between the client and server. The delegating relay does not implement a DHCPv6 server function. The delegating relay is also responsible for routing traffic for the delegated prefixes. It's generally done by having the relay be a passive observer of the DHCPv6-PD packets it is relaying between client and server, installing and updating routes for prefixes as needed. That RFC also goes into detail on problems with these setups. What you experienced was probably the loss of state described in section 3.2.