Comments moved to https://news.ycombinator.com/item?id=39832272 (which was posted earlier)

I'm confused. I posted to the exact same article (same URL) a day ago. The one on the homepage is from 9 hours ago and somehow points to the same thing. I didn't think HN would allow dupe URLs. I wonder why mine was ignored and the new post accepted?

Yours was the third submission of the article. You can tell this from the item IDs, as well as pages like https://news.ycombinator.com/from?site=512pixels.net.

What's confusing is that when we re-up a submission, the timestamps gets adjusted on the front page and the /item page, i.e. the thread for that story.

That's an artifact of HN's re-upping system. There are past explanations here: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que.... Sorry for the confusion—I know it's weird but the alternative turns out to be even more confusing (e.g. "why is post X on the front page even though its timestamp says 2 days ago and it only has 5 points?") and we've never figured out how to square that circle.