Hi,
Windows 8.1 wont refresh automatically without action taking. We wonder if you see some messages such like prepare for Windows refresh or colorful welcome screen.
In the other hand, refreshing need administrator permission to perform, try using standard user see if it happens.
Why use a standard account instead of an administrator account?
Whether you sign in to your PC with an email address (to access your Microsoft account) or a user name and password, for everyday tasks, it's best to use a standard account. A standard account can help prevent people from making critical changes, such as
deleting files that are required for the PC to work. You can create a standard account for each person who uses your PC.
When you're signed in with a standard account, you can do almost anything that you can do with an administrator account. But if you want to do something that affects other people using the PC, such as installing software or changing security settings, you
might be asked to enter a password for an administrator account.
Regards,
D. Wu