Richie--I'm not certain the shuttles are 24/7, they didn't use to be, but perhaps that was during Covid. They are definitely there for any times we have wanted, which is between about 9 am and 9 pm. They are very close to the airport, so it would be a very quick taxi ride, if the shuttle wasn't available. The shuttles are very prompt taking you to the airport and very prompt at picking you up, if you call them. Or they often are just trolling the airport and often have a shuttle there, just down the concourse. They help you with your bags. Upon your return, they bring your car to where the drop off is for the van. Can't recommend them highly enough. Do make a reservation online if you decide to use them, as they are often sold out.