>When this happens, the relative timestamps (X minutes ago etc.) are reset to the time at which the post is selected for the front page. The absolute timestamps in the tooltips, like you have discovered, show the actual time in this case.
Hover over the "minutes ago" string on any of those comments & you'll see the original timestamp. I guess this is a repost, comments got merged, and the "minutes ago" strings are cached/pre-generated from the old thread?
