Another Lufthansa 380 called in this morning en route from Houston to Frankfurt. Last one was positioning after a presumed tech issue, but this one just seemed to do a normal turnround in Houston after arriving from FRA, and then stop at MAN on the way back as a pre-planned diversion (LH website was showing the diversion yesterday afternoon). We've seen aircraft on long westbound trips calling in for fuel due to string headwinds, but heading east is unusual as the winds tend to be favourable. I also wouldn't have thought operating on 3 engines came in to play as it was at 39,000 before descent, and they wouldn't have dispatched it from Houston with passengers in that scenario. I don't think any of the Singapore flights routing IAH-MAN were cancelled so not dropping off their pax - the only other thing I could think of was crew hours, but that also seems odd given it wasn't that late out of Houston, presumably with a crew that had nightstopped.