I installed Akeeba Ticket core yesterday, and today was the first time that I had logged in to the backend since, and I received "Class 'FOF30\Utils\TimezoneWrangler' not found" error as soon as I logged in.
See attached image.
|Joomla! version (in x.y.z format)||3.8.2|
|PHP version (in x.y.z format)||7.0.25|
|Akeeba Ticket System version (x.y.z format)||2.4.0|