I agree there's no error. It's letting you know there's an overnight. There's only one flight from SFO-BKK and it departs AM not PM. As the previous poster pointed out 24hrs or less is a standard connection for international. Since it looks like you're looking for reward tickets this might be the only standard award routing, while something else (East coast-DTW-NRT-BKK for example) might be available but only for rulebuster.