The 2019 rules require four sails on board - mainsail, Genoa, jib and spinnaker. For a three day regatta, must I use the same four sails? For example, if there is a blow forecast for the first day of a three day regatta, I would prefer to place my 135 headsail on board instead of the 150. The if the blow is over on the first day, I would like remove the 135 from the boat and place the 150 on board for the second day. Is that allowed??? Are more than four sails allowed on board . . . with the four listed sails the minimum allowed on board?