Is this required? I don’t have Outlook, but VSS (i.e. –snapshot-policy=on) can likely backup that .pst at 1pm. VSS can sometimes go wrong, and Microsoft excludes the .ost deliberately, but it might be the easiest way.
More:
Duplicati and VSS
Troubleshoot backups of Microsoft Outlook data
Is Outlook compatible with Volume Shadow Copy Service?
I’m not expert in Task Scheduler, but Windows is always waking up my desktop to do things, and if you can get a task to run Duplicati from the command line then go back to sleep, that might be an alternative option.