General

familiars expiration date

before there was some kind of expiration date on familiar cards, and upon getting more of the same, the durability were increased.
EX: like 3 jr boogies, could stay up to 90 days, and then you'd have to hunt for them again, since they disappeared from the monster book.

but now i don't see any of these numbers. will they stay forever in my book?
i want to that ToT card i found

thanks in advance!