Mine waits roughly 0 to 5 minutes, and my suspicion is that it’s in below time-limited scheduler wait:
I have an hourly backup, but I looked at the last 10 morning wake-from-sleep. The delays from wake:
01:21
00:49
00:49
04:27
03:16
03:43
04:31
01:41
01:53
01:56
That’s 2:27 average, which fits well with a random delay (depending on timing) from 0 to 5 minutes.
Wake times are in Event Viewer in the system event log as Event ID 1 from Power-Troubleshooter.
Easier method is powercfg /sleepstudy or TurnedOnTimesView (if you don’t mind third-party tools).
I got my backup start from The operation Backup has started in a log-file >= information level.
Is your system quite busy when it wakes up, e.g. if you look at Task Manager CPU and disk usage?
Some people also like to deprioritize Duplicati with thread-priority and/or use-background-io-priority.
This may possibly account for some additional delay in Duplicati getting going. How do you start it?
However you start, what happens if you stop it before sleep, and start it again after system wakes?
“Pause after startup or hibernation” does not work #3693
Possibly this only works (and it does) on Windows? There's a lot of Win32 usage in
https://github.com/duplicati/duplicati/blob/master/Duplicati/Server/LiveControls.cs