I'm unsure if this is a bug, so thought I'd post here first to see if anyone can confirm.
See screenshot: http://smbmedia.co.uk/WordPress-bug.png
I believe these links (as default) should always be the File URL, and not the Attachment post URL.
Can anyone confirm?
I also find it very odd that with an editor account, it varies between the two. 9 times from 10, they're added as Attachment post URL but occasionally they're added as File URL.