IIRC, there were several references in Season 5 to Franklin leaving "at the end of the year", or of other stuff in the show that was due to wrap up the story "at the end of the year". It always struck me as strange that no one ever varied the phrase-ology, like saying "in December" or "in X months".
Actually, did they ever refer to specific months in B5? I know that in "Deconstruction of Falling Stars" there are references to specific dates, as there are in Crusade. But other than that, does anyone ever refer to months by name? Or for that matter, to days of the week by name? (Granted, TV in general is pretty bad about doing that.)