>My actual use case is where weights represent nodes in a transport system and for a person arriving at a vertex at some time Tx, there is a variable weight of using the next outbound transport = waiting_time + travel_time, where waiting_time is a function of Tx.

That sounds like you intend to calculate a *dynamic* shortest path, which is not what Dijkstra's algorithm does for you.

I know it doesn't answer your question, but I think it is more pertinent.

Kind regards, Alex