Note, however, that mixed cabin awards are not available. (rewardexpert.com)
You can book one - way award flights for half the cost of roundtrip tickets, pay for up to 60 percent of a ticket with cash and mix cabins on award itineraries. (rewardexpert.com)
They don't allow mixed cabin awards, meaning if you book a business class award all segments have to be in business class (onemileatatime.boardingarea.com)