I'm using Google Photos to backup and sync my photos to the cloud. In the menu in the Android app there's an option called "Free up storage", which will supposedly
Remove original photos & videos from your device that are already backed up.
Clicking it brings up a dialog that says
Free up 12.46 MB
Remove 6 items from device
These items have been safely backed up to your Google account. You'll still be able to view them at any time.
This makes no sense at all, considering I have backed up 500+ photos using the app. They all appear at https://photos.google.com so I'm 100% sure they are backed up. Of those 500+ photos, only 31 are recent ones (less than 30 days old) and the rest are older, up to a year old.
Why does it say that it can only remove 6 photos and free up 12 MB? Is it because my phone has 3 GB free internal storage and 20 GB free SD Card storage already?
I am aware of the "Delete from device" option to delete individual photos, what I'm interested in here is how the "Free up storage" feature works, and why it won't actually free up all the backed up photos.