Under Settings -> Backup -> Frequencies and versions

Move the "Remove deleted files" down to a lower setting.(to "every day" if you want)

You could set it 0 let it delete all the files and after that is complete move it back to whatever you want.

You could temporarily or permanently reduce the time to keep backups. Unfortunately, this is a system wide change and would not just effect the one folder.

1. Under Settings enable backup sets.

2. Create a set for this folder and one for everything else you backup. For example: 1. Everything excepts logs 2. Logs (/home/user/)

Each backup set has independent settings!! 3. Under Settings -> Backup -> Frequencies and versions You can set the first one to a year. Set the Logs for whatever you want.

When you want to delete logs move the slider down to every day. Wait 24 or 48 hours. Move the slider back to previous setting.