Well ATL-NRT and MSP-NRT are basically full up front on 5/31. The NRT-SIN flights are full up front also for travel then. DTW-NRT is the only one with availability right now.
Can you leave on Friday 5/30? Much better availability in coach and BE all around. In fact there is currently 1 seat for upgrade available on 5/30 for ATL-NRT.