Just realised that I meant to say Task Scheduler - una pava distinta de pescados!!! Same task as Windows 7, to record BBC radio webstream using ffmpeg, for a specified time. I played around with the settings without success for some time until an error message appeared asking if I wanted Windows 10 to do exactly what I was asking. I clicked Yes and the Task Scheduler settings were changed automatically - then it worked! The settings to shut down the PC worked as for Windows 7.