My blog server runs WordPress software, which I can update hourly while the server is running, if necessary. However, the underlying Apache, PHP and MySQL software requires server downtime to update, so I have scheduled their updating to take place in the evening (UK time) of Tuesday 17 July 2018. I am hoping it will only take 1-2 hours to complete, but, having never done this big an update before, I can’t be more precise.
Apache, PHP and MySQL updates have been completed successfully. The only loss was this warning post, which I’ve re-issued and added a comment.