will be booking FWA-DTW-NRT-TPE pretty soon, very likely in M class to use these SWUs (already checked that U is available on the dates I want). Does anyone know if it's one SWU per trip (so, 2 SWUs total for the round trip FWA-TPE and back), or is it one one SWU per segment - meaning that I will need one certificate for DTW-NRT and then another one NRT-TPE?

couldn't seem to find this anywhere.