I posted this to Bug Reports, no idea why it ended in Gameplay Help

Just for completeness, in my setup I have 3 kinds of station, IMPORT, EXPORT, and PARKING
All trains have schedule:
goto EXPORT until cargo full
goto IMPORT until cargo empty
With an interrupt:
If no path, goto PARKING

I would love to be able to add a condition to the interrupt:
(cargo is empty AND ...

One could consider this to be a feature request for a "there is a path to station" wait condition
Though I'm not sure when would you want the current "station is not full" and wouldn't want a "there is a path to station"

There is an interrupt condition "Destination full or no path"
There are also similar sounding wait conditions "Station is (not) full"
Unfortunately the wait conditions don't emulate the interrupt condition

Consider a situation when you have disjoint rail networks, with same name stations
Within ...