Considering that it can be a good 8 hours of mixing per song, I'd venture to guess that with the complexity of QR's music, the many layers, it'll push the 10 hours per song mark.
You have to eq/comp/pan, pre-program fader swells, fade outs, aux-sends/return levels per event, etc... Even though much of today's mixing occurs "in-the-box" meaning "on the computer" there are envelope assignments for each parameter, practice runs, troubleshooting, references listens on multiple speaker sets to ensure mixes translate to each listening environment objectively. Lots of notes get taken. It actually used to take even longer when analog mixes were done completly live, by hand.
Mastering can take a bit less time, but it's also time consuming because you're trying to maintain some level of continuity in volume/tone/character from song to song to ensure that the band "sound" is relevant, all the while trying to give each song its own character and identity.
As a rule, I never mix post production on my own music, just to get objective ears involved.