Arrow does not permit more than 3 adults in any room type. There is no agent discretion and doesn't have anything to do with meals. A normal full-size mattress is 53" across. The lower bunk in both Viewliner and Superliner bedrooms is just 40" across. Two people just won't be comfortable, or even fit, on the lower bunk. There is no distinction between day travel and night travel, either.