Today I was running out of space, so I decided to delete some of my oldest manual backups. I had a mixture of remotely stored backups and local story backups. I selected the oldest ones, the ones that were 10 months or older, and then I clicked “Delete.” Then, to my surprise, only one backup remained, despite leaving unselected at least 12.
This is the screen where it happened:
I think this could be a bug in how the selection is handled.