If you're sure that your settings are correct in the admin panel, on your profile and in your php.ini file, there is a fix for this bug that I finally found on this forum two years back when our time would be one hour ahead during US Day Light Savings time. I just noticed that the issue had reappeared, and it was because I forgot to apply the fix after updating to the latest OSTicket version. Here is the fix that works for me:
PROCEDURE
Edit mysqli.php file, which is in /public_html/support/include/mysqli.php
ORIGINAL
» From this section line 119, change from
return db_get_variable('system_time_zone', 'global');
» CHANGE TO
to
return db_get_variable('time_zone', 'global');