I suspect that the ~1 day delay is just the time needed to run automated tests, rebuild packages, retest them, upload them on the various channels, turn updates

I suspect that the ~1 day delay is just the time needed to run automated tests, rebuild packages, retest them, upload them on the various channels, turn updates on, etc. I've worked with people who work on release engineering. Many things can go wrong by accident and silently, so you take your time to avoid distributing a broken binary that you could not upgrade.