Thanks in advance for your help!
It's a long topic (though not thát bad), the main part is in page 2 and 3, it's chronological, so makes sense to read up from there. Otherwise I'll just repeat myself and the topic gets even longer.
I've encountered the fail a few times now and I have to manually intervene / restart the scheduler if I want to keep it going, otherwise it gets stuck after one, and maybe two jobs (of four).
Again last light this happened:
In this instance, two jobs of 20 lights each were executed, but it failed to continue (there was plenty of 'night' left to continue though!) The jobs currently count 40, 41, 40 and 40 lights (failed at the last 40-th light).