Have sailed several times in NCL. Have stayed in various accommodations. I do remember once booking an inside on a lower deck and being upgraded to identical cabin on a higher deck. Only two in cabin however. When only two NCL has more flexibility. When upgrades do happen, it is normally for an inside to an outside or a outside obstructed to an oceanview unobstructed. End to middle type of thing. If you are expecting to be upgraded from an inside cabin for 4 to a suite with a balcony, you are dreaming (sorry about that). NCL is not in the business of fulfilling dreams when so many people pay for their "perfect" cabin. Just my thoughts on the whole upgrade thing. Four people will be tight in a NCL cabin. NCL may have some family cabins which are larger. Have you tried asking the price of those. Sometimes it is better in my opinion to pay a little more for the convenience and get really what you want. A vacation is a vacation and sometimes worth the extra cost for peace of mind. Maybe all will work out fine and you will be one of the lucky ones to get moved to something special but don't count on it. Cheers.