Not very likely. But there aren’t really rules on timelines for modnotes.
If it had been a warning it would be rescinded in this case as it is well past any arbitrary time limit for warnings. That is probably less than a week, definitely less than a few weeks.
No, no need. But there are some exceptions to this.
We had a prolific poster caught up in his own many lies about himself. Some pieces going back many years. It was solid proof of their trolling the board and they were Banned. Said person has probably come back a few times since and may have had another Sock Personality banned today.
But that is an extreme case, we don’t need to know someone used an offensive term 4 years ago and didn’t get modnoted or warned for it.
Though if the person makes a habit of such, a link to older examples in a current flag is much more likely to lead to moderation. That happened in the case of a few posters that were then warned instead of modnoted and no surprise later warned again and suspended and finally banned.
In general links are useful. I know what you’re talking about in this case, but often I wouldn’t and I’m sure plenty others don’t.
It looks like all of the confusion today was caused by the dumbass way dates are displayed by Discourse. Your post read Jul 21 instead of Jul 21 2022. Probably wouldn’t have been flagged if the software wasn’t dumb about dates and probably the flag would have been rejected as happening 364 days ago if the software wasn’t dumb about dates.