Recently received this great game but I have just a half learning play in my experience up to now; so, sorry for a very basic question:option B. They become ineligible immediately when the event is executed and "through next card" means that they will become illegible only after the next card.
in case we have in eligible box arverni and romans and a card such as "sacking" is played as event by Arverni (romans ineligible through next card), this means that:
a)romans are ineligible for present card (they were eligible and second in the card faction order), and are again eligible for the next card;
b)romans are ineligible for present and next card
c) romans play regularly this card (when possible)but will be not eligible for the next one.
Thank you all for your help
See also this thread: https://boardgamegeek.com/thread/1652059/ineligible-through-...