Just want to share my most recent upgrade experiences. I booked a return Mel to LHR. I put in an upgrade for both legs. The upgrade from PE to J came in at around 23 hours prior to departure which was great.
For the return leg I decided to cancel my upgrade, give PE a try and save some points. This was on QF10 departing London Sunday 22nd April. However, the flight didn't depart on time. The first delay was due to one of the pilots not feeling well enough to travel! The second delay came about from a fault with the plane. Those with status were sent back to the loung with no estimated time for departure. 2 hours later we were told that we would be departing the following day!
We were transported to hotels. I did however find out from one of the ground staff that I hadnt been transferred to the 'premium' hotel as there wasn't enough room. I called Qantas to explain the situation and requested an upgrade. They advised that this couldn't be done as there was only 1 seat left in J for LHR to Mel. I was aware that there were plenty of seats SIN to MEL but I was advised that they could only upgrade the whole ticket.
I arrived at the airport the next day and spoke to the rep at the gate. Once again she advised that nothing could be done. We had a polite conversation and I went back to my seat. 5 minutes later she came back to me and said that she was going to attempt to help me. She came back once again with a J boarding pass LHR to SIN and advised that she couldn't help with the final leg. A pretty good result i think!
I arrived in SIN went to the lounge for a shower. Once again I thought id try my luck with the rep in the lounge. I explained my situation and he said that he would call through to see if there were any notes on my booking about an upgrade. After a quick phone call he went to the computer and printed out a new bp for J! So all in all it was a pretty horrendous delay - 14 hours! But I at least managed to do it in J!