Yes, airlines will add/reduce the number of flights between locations depending on the season. For example JB has a flight that runs from SEA to Anchorage from about May to Sept only. Other city pairs may have 5 non stops in the summer but only 3 in the winter or the opposite. I don't know if they have reduced flights before between PVD and MCO though, but I don't believe they have. For example they could have looked at psgr counts the past couple years and realized it was not worth running 2 flights a day in the summer between PVD and MCO but the BOS to LA market needed another flight so they could have added a flight between BOS to Long Beach.