@Alistair Russell
According to the configuration above, the clients will check, download, and install updates automatically at the schedule time if there are several updates waiting for installation.
Of course, the clients(windows update agent) will refuse to install updates if the clients are in active hours or there are something wrong while clients are downloading and installing updates and fail to install updates currently.
Please review the windows update log on the client if you want to confirm why the updates are failed to install at the schedule time.
Hope the above will be helpful. Have a nice day.
Regards,
Rita
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