@quinn interesting here they prefer to give them their normal route numbers but with the caveat that they will deviate from the route at one point, so you get stuff like this, and it's pretty much how it works in every city with trams here
They sometimes do something similar here, when a tram can go to the depot without deviating from the usual route, i.e. sometimes I see 1E Tullastraรe, but only if the usual line matches to its end.
@quinn yeah here they do not do it like this, on the timetable at the stop you'll get another letter for it and it will say last stop of the normal route, and it is still stopping on every stop on the route to the depot