Error on desktop is nothing. The page just doesn't load.
The gateway did not receive a timely response from the upstream server or application.
Then, reload the page a few minutes later and the site opens. It must time out???
The .maintenance file is NOT in the website directory. No updates were being performed.
Other sites still work fine.
I did notice that there was a touch of weirdness. On mobile, I type in the URL, Blog.SwimISCA.org. But the site flipped three times to another site, Read.SwimISCA.org. That might be a function of the iPhone?
Support wrote to report:
The issue actually appears to be related to caldera. When you made your most recent edit, it issued several queries to the database related to caldera which basically held the "wp_options" table captive, resulting in
the page being unable to load. This was so severe that we could not even get the WordPress command line interface to list your plugins till the MySQL processes were killed.
We can try moving your database to another database server, as mentioned yesterday, but it is not clear if that will have any impact on this issue.