I recently discovered the --suffix and -- backup-dir parameter which are usefull to make incremental backup.
Some people suggest to use the --suffix parameter with the current date, however this will make the "old" file use the date of the synchronisation and not the date of the file. For exemple if you have a file last updated in 2020 and you use the --suffix parameter with the 2023 value your file will have a 2023 suffix even if a 2020 suffix would have been more logical.
For this reason, it would be nice if there was a way to tell rclone to use the last modification date of the file, that way a file last updated in 2020 would have a 2020 suffix and not a 2023 suffix. More exactly I used years in my example but it would be more logical to use the date (2020-10-28).
A possibility would be to add a --suffix-use-date that would enable this behaviour, or a --suffix-default=date (or --suffix-automatic=date) if we want to allow different automatic behaviour.