Welcome to the forum @SteveRoome
The synthetic filelist is intended to be made at start of backup when previous backup was interrupted, meaning possibly you began and stopped one earlier before launching the first real backup. Possible?
The filelist, as its name implies, is the list of files in a backup. After an interrupted backup, you can get whatever was in the previous backup plus whatever was backed up before interruption. This is the list.
Above is how it should work, however it’s possible initial backup is different. There was also a bug that
manages to do one lookup incorrectly, thereby preventing the synthetic filelist. This got fixed in Canary.
This happens if you use “Original location”, and the file is already there, and everything is as requested.
The file is examined as it sits. If no action is needed to restore it to desired version, then none are done.
If restored file is different, it gets timestamped in your case. For
Overwrite, original is patched in place.
“How do you want to handle existing files?” is irrelevant if file is already fine, but language is misleading.
Overwrite has nothing to do if file is OK already. I’m pretty sure Duplicati optimizes out needless work.
One that can interfere with optimal restore testing is that restored file blocks are gotten locally if present unless –no-local-blocks is set true to force it to actually download from remote instead of using locals…