Some items can show up in multiple review queues. This answer in particular showed up in the Late Answers review queue.
At the time it also had a suggested edit pending against it. I hit the
edit link, at which point I was forwarded to the same question but in the Suggested Edits queue. I approved the edit, then nothing further happened. I then refreshed the Late Answers queue, and found the same question still there, but now showing one approval (mine) for the edit.
If I select to edit a late answer, and there are no current pending edit approvals then editing the post will be done inline and cause the
I'm Done button to light up. However if there are edit approvals required, it is executed within the context of the Suggested Edits queue, I am no longer within the Late Answers queue, and the action I took doesn't count within the Late Answers queue.