If you do not need a specific snapshot on your WordPress site, you can quickly delete it:
- Open Tools -> WP Reset -> Snapshots
- Scroll down to the "User Created Snapshots" card
- Select a snapshot & open the "Action" menu
- Click "Delete snapshot"
- Confirm that you want to delete it by clicking the red button
This action will delete a snapshot from your site, but if you have the snapshot offloaded to a cloud of your choice, you can always restore it. You can also delete a snapshot from the Cloud by selecting the "Delete Snapshot from the cloud" menu option.
Please note that once deleted from the site the snapshot is gone. There are no additional backups and no way to get it back unless you have it stored in the cloud.