Also, even if you get your 8 hours say from 8 AM till 4 PM, waking up and only seeing night time several days in a row messes with you mentally. Day night transitions really mess with you as well. I though pax domestic flying was rough sometimes.. This takes it to a whole new level. Just the other day I woke up at 4 PM for a 1:30 AM shuttle. 3 AM airborne, back in the hotel at 4 PM. 24 hours awake. I sleep good during the day but this stuff gets to you quickly.