I realize this is an open-ended question--I'm not asking on behalf of a particular customer--but we're wondering if Windows 10 always respects the GPOs we've set for Windows Update, which point all domain PCs to our on-premises WSUS server with specific maintenance windows and restart settings.
I'm hearing anecdotal evidence that 10 may bypass WSUS (and any other WU-related settings imposed by GP) and update and restart itself whenever Microsoft deems this necessary. I don't have "smoking gun" proof yet, but cursory Googling suggests I'm not the only one who's getting suspicious, and we're seeing some erratic update behavior on our fleet of Win 10 Surfaces.
What has your experience been like? Do you use WSUS, or a third-party patch management solution?