If after upgrading a plugin on your WordPress hosting, and WordPress gets stuck in maintenance mode, there is a simple fix.
The message you’ll get in WordPress that never goes away…
Briefly unavailable for scheduled maintenance. Check back in a minute.
When WordPress puts itself into maintenance mode, it does so by creating a file named “.maintenance” in the root folder of your WordPress site. This is the same folder that contains:
To fix the WordPress stuck in maintenance mode problem, you’ll need to connect to your server via FTP and delete that file.
For those interested in what such a file might look like, it appears to simply assign a PHP variable $upgrading with the current Unix timestamp.
<?php $upgrading = 1569312968; ?>