-EDIT-
Aw crap, just saw this reported in the collected bugs thread.... my apologies.
Playing as the Casse. Following the Summer or Fall of 264 B.C. when I press end turn, after the AI is done the date turns to 14 A.D. and the end-game screen pops up. All the technological advances or whatnot icons appear on the side that would have appeared I assume up to that date. However, the date turns back to 264 B.C. after all that, but the damage has been done.
-edit-
Oops, it's actually during winter, and pretty certain it's a scripting issue. I loaded a save-game from the winter of 264 B.C. and when I activated the script, the date turned to 14 A.D. and the climate on the map changed to non-winter.
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