What happens is the following: You backup at 20.00 (and I assume it shuts down then...)
When you boot up in the morning, it reconnects to the target and does a new backup. The reason why is since you are using a combined schedule...
Not only at 20.00 PM, but also when the computer connects to the backup target (which happens because you start again). Since the last backup is older than 4 hours, it will start again.
Our scheduler is OR so that is the reason why you have this.
I am not sure though why it is only happening on windows 10 machines