National - Premium v. Luxury

I have a week long rental at IAD in July and currently have a premium reservation. I noticed today that the had luxury available, and was curious what the difference would be. Most of the cars on the ride report page that are listed as luxury, are either gone or soon to be gone (ie Town Car, and CTS). Most of what I would put as luxury are listed as full size elite. Is that the new luxury? The price difference is about $30 for the week, and I am Exec Elite.

CTS is back... I've seen some recently at MSP and SAT. Most of the time with a Luxury res you will probably get a full size elite, or some othe level of "elite" car.

Premiums are Avalon, Maxima, 300, LaCrosse, Taurus, Genesis, Accords, and possibly some other ones here and there. It is also possible that you could find/be offered one of the elite classes on a premium res.

I rented a luxury at IAD in may, got the new MKX base trim. They had a 328 out front as well but it wasn't offered. I'm only interested in the new 328 so I didn't ask.