"Unique Visitors" and "Delete old Tracking Logs"

Hi there

I’m completely new to Matomo, so I don’t fully understand the way Matomo works yet.

Our Matomo-Server is running low on disk-space. So we found the option “Delete old Tracking Logs” which sounds good, as we have 4 year old records in those tables (Around 20G). But. We want to have yearly “Unique Visitors” reports. So.

Does it work, if I setup enable_processing_unique_visitors_year = 1, forcefuly reprocess all reports (+ archive) and then set the “Delete old Tracking Logs” to 380 days (a few over 365)? (Auto archive is enabled)

Wouldn’t that mean, the data get’s saved for at least a year, the year report could be generated and the data get’s deleted when it isn’t used anymore?

If not, is there a way I can at least generate the year reports and run the delete logs just once?

Thanks a lot for any help you can provide!!!
Regards, MS