My recent experiences (April/May) before the changes:
LAX-JFK: waitlisted about 3 weeks before the flight. Cleared 2 days before flight. Business to First Class for 8,000 points
LHR-MEL: waitlisted about 3 weeks before the flight. Cleared some time in the few hours before the flight (not cleared when I tried to check in at FRA, was by the time I reached LHR Flight Connections transfer desk). Business to First for 55,000 points. SIN-MEL section was showing F0A0 for several weeks. The f cabin was full for the SIN-MEL sector, 3 or 4 seats free for LHR-SIN sector.
MEL-SYD: Z was available 3 weeks prior when I requested so no waitlist. Business to First for 5000 points. I was the only passenger in the F cabin for that flight.
And from November last year:
SYD-LAX: Waitlisted 7 days before flight. Cleared 5 days before flight. Business to First for 4 x Upgrade Credits.
If my next ticket gets issued today I will be joining the waitlist for SYD-LAX in F for a flight next week. I will let you know if that is successful.
I guess I have been successful on about 80% of my international upgrade waitlists. But I do try to select the flights/dates/times that are more likely to have space in F (ie avoid Friday-Monday flights).
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