I'm approaching the Dec 29th departure of my flight that I now have 4 different waitlists for F on the A380. My preference is the DXB-YYZ flight but I was told by an agent today that there are only 3 revenue seats left on that flight so she didn't think my odds looked that good. The direct JFK flight had 4 revenue seats and the MXP connecting JFK flight seems to have availability on the DXB-MXP leg but not the MXP-JFK portion (yet). The agent seemed to think that I'd likely have the most success on the JFK flights (assuming I am successful at all).

I had thought that on the day of travel, that any available seat (award or not) becomes available for use by those on the waitlist. The agent said that's not true. Anyone with any experience as to whether I should hold out until the day of departure and just show up for the flight I want? Or will the waitlists all get cleared the day before/day of the flights?