You might know about their public appearances such as for shareholder meetings but how would you know which hotel they're staying at and that they would leave said hotel at 6:45 AM(!) and walk(!!) to the meeting venue?

Either massive luck on the shooter's side or there is a source of information that hasn't been discovered yet.

If real, he scheduled a post to be released everyday at ~6pm EST. If he wasn't caught that day he would delete the scheduled post, and reschedule for the next day at 6pm.

I say 6 because it was the earliest snapshot of the site. Looks like the post just got taken down off sub stack and I can't view the exact time of post.

That's likely how it happened