If you look at Kosmonaut's profile, you will notice that his only question shows "jan 20 at 0:29" as timestamp.
If you look at the question, Central Pennsylvanian English speakers: what are the limitations on the "needs washed" construction? you will notice that Lauren Ψ edited the question on Aug 2 at 17:31, and she didn't answer the question.
Does the timestamp show a different date to avoid the question is bumped on the front page, or is there something more behind this?
The entire CHAOS Team was given edit privileges, and since they were fixing at least 1000 questions these edits did not bump a question. This means that on a particular question, you can see when it was edited. But, on a user's profile, you can see who edited but not when. I think this may relate to how "bumping" works--in this case, the timestamp which bumps a question was not updated.
This phenomenon happened with other members of the CHAOS team. For example, this question on Apple was edited in early August, but the user's page shows the date on which the question last received a non-CHAOS edit or modification.
