The problem, however, is that I can't recall where I made this change. I feel like I have been through every page in the ACP and still can't find it.
I'm also using CGCalendar and that is also showing a day ahead.
Thanks for any help you can provide.

Also, as a side note: I have tried changing my .htaccess page as some have suggested, however that did nothing for me. I have cleared my cache both on the site and my personal browser cache, with no positive outcome.