Ohh...upgrade from a revenue ticket

I asked. This one's easier to run via an agent:
Me: "OK, case 1: I've redeemed a one-way from HKG to SYD whilst waitlisting for the return. Return cleared when I was in SYD. Your colleague deducted me two one-ways and then refunded the difference between the two one-ways and the return. This can still be done right?"
Tsuen Wan Agent: "Yes, this can still be done. You have to complete the two one-ways of course"
Me: "OK, case 2. Same case, except I am upgrading from a revenue ticket. Outbound clears early but inbound cannot be upgraded until I'm in SYD. Any similar refund?"
Agent: "Yes, similar refund can be applied for upgrades also after travel"
Me: "Does it matter if my Australian outport is PER?"
Agent: "No matter, still round trip"
Me: "And can I start and stop this trip in Japan instead of HKG, and not upgrade the Japan-HKG segments?"
Agent: "Might still be counted as a Zone C upgrade. But we have to see your revenue PNR to confirm this can be done."