years ago I recall Layne talking about fasted a.m. cardio as being counter intuitive to what the bodybuilders were doing at the time (waking up ever 4hrs to refeed). He was like "these guys are working so hard to stay in a fed state every 4 hours, then for some reason risking catabolism to do fasted cardio in the morning". I don't want to put words in his mouth but you get the gist of it.Being fasted doesn't really do anything special for your cardio other than possibly feeling better not having a full stomach. The benefit to fasted cardio is often confused with the benefit to doing cardio earlier in the day, and your metabolism being sped up after for longer. Evening cardio the body's circadian rhythm automatically tells the body to start lowering metabolism for rest as bedtime approaches. So you just don't get as long with a raised metabolism. Not a huge deal but being fasted really is not a game changer in any way. The topic has been beaten and studied to death, and those are really the only statistically significant differences which are very minor in the big picture. Fasted or not, your body still has plenty glycogen left to burn off in those first minutes of cardio before things start turning to fat burning a little more predominantly. Plus when it comes to creating a deficit a burned calorie is a burned calorie. So no worries about whether or not cardio is fasted.
I thought Hubberman had talked about the benefit of cardio when doing prolonged fasts, or reaching for ketosis, but that example is a bit more extreme than 8-10 hrs of fasting during sleep.