I think this should be a feature of HN:

Automatically post previous posts of the same article

It sort of exists already. There is a "past" link under the title of the submission that lists previous submissions.

you can already get this with the "Refined HN" chrome extension

Firefox as well, not just the adtech browser.

It’s what I usually use to post these, but this time I was at my parents and remembered that I had seen this before, so I used the search ;)

with archive.org links and diffs.