This is the case study of the value of a DAILY Sunset Ltd.
The PRIIA study in 2009 or so that looked at the Sunset (like every other every LD route) reported that efforts had been made to interest limo/van/bus operators to connect the Maricopa station, the major hotels, and the airport.
The operators already doing business at the airport were all interested -- if they could use their crews and vehicles 7 days a week. Otherwise, their equipment would sit unused 4 days a week.
Meanwhile a new station at Maricopa has been funded, largely with Arizona Dept of Highways money, to their credit, and a federal TIGER grant.
Presently, the trains using the station block the UP's main line, but a new track will be built to serve the station. And presently, to discharge and board, the Sunset Ltd has to stop two or three times to fit the very short platform, making for longer delays to the freight traffic and the passenger train. Meanwhile, the stopped train also blocks a main street/state highway, messing with the morning commuters.
So a new and better station, with a new track of its own, in a new location, with an overpass to take drivers across the tracks ...
Soon all they will need is DAILY service and then limos, vans, buses, and taxis will link exurban Maricopa with central city Phoenix and the hub airport.
The PRIAA report forecast that a DAILY Sunset would see the route's ridership double, by more than 100,000 passengers a year. I expect ridership at Maricopa (Phoenix) will triple the present levels once the service is DAILY.
iirc The funders hope that the moving and rebuilding will be done by the end of 2018. I can't see a DAILY Sunset before then, but I expect to see it a.s.a.p. after that. It will probably depend on the actual deliveries of the Nippon Sharyo bi-levels to free up some equipment.