This might be a solution for you:
https://wordpress.org/support/topic/utc-time-and-local-time-problems/
It says that it’s a problem with PHP config, not WordPress.
(Bringing the solution here for ease of reference)
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If you have shell access, do you get the correct date/time when you type “date” at the command line? If that’s wrong, contact your host.
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Try adding the correct timezone to php.ini: http://www.inmotionhosting.com/support/website/php/setting-the-timezone-for-php-in-the-phpini-file (And check if that is displaying the right zone)
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Check your plugins, if any of them modifies anything on WordPress clock. On the link I sent above the case was solved by deactivating a calendar plugin.
Both these links below can help with your search too, I can’t point at what could solve it since there’s missing information on this topic about what they say there, but I hope it shine some light into your problem!