This is something I wanted to ask as well. My wife has a recent trip YVR-HKG-SIN-HKG-YVR on one ticket, staying in HKG after the first leg for more than a week, then to SIN and back and each stop staying a few days. I always thought for a trip originating from North America, baggage allowance will be 2 pieces throughout the trip. But her ticket shows 2PC for the long haul segments and 30K for HKG-SIN-HKG.

Is it something to do with the stopover not treated as a connection any more and what exactly is the rule?