I think 1-up and 2-up are modern terms that refer to the number of people aboard. It has nothing to do with the hull shape or number of sails.

Cat rigged on the other hand is a much older term and may refer to a specific type of boat. I think a "cat" boat was originally any boat with maximum beam at the bow. Later it became any boat with one sail and one mast.

http://www.catboats.org/ This type is an American original, used for fishing in New England.