@gcampo
It’s only a 5 minute wait time as the travelers stay in a building for a certain amount of time before traveling again; This means that the only thing you really have to worry about is how long it takes to get from one station to another in a multi route line and if it is evenly dividable by 20. If you have a route with 10 stops you want the total time under 200 minutes (3hours and 20 minutes).
This also considers the time it takes to travel TO the station before hand and FROM the station to the destination.
So for a 15 minute trip it would be 2.5 minutes to travel to the station and 2.5 minutes to travel from the station.