We've always had some issues with incorrect dates for some users. All should be fixed as of today. Please go to your settings and check if your timezone is the correct one (most likely the GMT offset will be the correct one but you'll have to update your location). Here is what's changed:
Homepage lists (Watchlist, Today/Tomorrow/Yesterday, right bar calendar) and the site Calendar should now correctly arrange shows according to your timezone AND the show channel timezone.
in Episodes, the episodes should appear right after they air. This worked well on a day level before, but wasn't as accurate, especially for some users and shows.
On series details page, the countdown is vastly improved, getting local and channel timezone into account, giving you the exact countdown till air time. Also, if local timezone is different than the show channel timezone - a local Date and Time is being displayed for Previous and Next episode.
Nothing revolutionary for most users, but vast changes under the hood, so please let me know if all looks and works ok for you! If not - describe the issue and I'll fix it ASAP!