the 2 day tickets that do not have "free" days on them, do not expire.
you do not have to use the days in any time frame
if the pass such (as the 5 day one that is presently being sold) has NEVER been used, then it will not expire.
once you use a pass that includes bonus days, iwill expire 4 days after the first use.
about disney, you have to pay to have their passes non expiring.
i bought a 10 day pass and it cost $100 to have it be non expiring.
disney does not give anything away for free.
universal does not have that add on like disney offers.
i guess it would be as cheap to buy the special 5 day pass for universal.
at the cost of daily tickets, even if you went only 2 days, it would be cheaper than the 2 day ticket.