Acronis BR 11.5: Does not delete the older backups, free space is filling up

First, now the last backup is exactly 7 days old. Did you let it create one more backup to check if it deletes the last one then? If it doesn't work, it's wrong because it should.
With simplified naming you will have only one full per backup, in case if you do not use [date] template. As you have full backup scheme, this means one backup at all - the latest. With [date] template you will have to delete older manually using some script, in pre-, post- backup command or run independently by schedule.

Well actually it keeps all backups, but I deleted some to free space, i have tested up to 13 days and HDD was almost full.
I was thinking to create 3 backup plans (tuesday, thursday,saturday) with simplified name so it can ovewrite, instead of using the current backup plan which runs every tuesday,thursday and saturday.

In general I just want to have only the latest 3 backups available for my workstation. Will the 3 seperate backup plans with simplified name work (overwrite themselves every time they run)?

Thanks

Three separate backup plans with simplified naming will do the job, but while backup task is in progress and the previous backup is already deleted, you will have only two valid backups.

OK, that's what I wanted.
Thank you