Since I installed the “Windows 10 Fall Creators Update”, build 16299, the desktop has stopped auto-starting, to it’s BIOS configured schedule. It’s scheduled for a 5:01am start, but every morning I’ve come into the room, since the update, it’s sitting there switched off.
A couple of Google’s later and here’s the answer, well I hope it is as I haven’t verified it yet, something for tomorrow morning. So the suggestion is to disable Windows “fast startup” mode, details on doing that can be found over at TechAdvisor.co.uk, and a more detailed explaination of why is at HowToGeek.com.
29th October 2017: Seems to have resolved the issue.