I am trying to book this trip for June 2017 using United miles 1. SFO-EWR-ATH (stopover) 2. ATH - VIE-HKG (destination) 3. MNL-ICN-HNL economy on the 1st two lets and business on the way back... 100K United miles. Would it be possible to add HNL to SFO for less miles? Is that a valid routing?