Apparently one of the lemmy.ml admins was overzealous in banning all User-Agent strings that contained the string “bot”. Bans were entered for all of the individual strings containing that word which were observed in their webserver logs, which impacted kbin’s reported agent of “kbinBot”.
The issue has been fixed, and I observed that one of my kbin posts to a lemmy.ml community was successfully pushed to the original instance.
There were a number of people who’d claimed that they reached out, but whether the admins saw those messages is a valid question. Assuming the best seems best for now… though I do understand why people might find the entire situation a bit odd.