I booked a last minute flight on CX (long haul) departing in the next 24 hours showing J2C2D2P2I2. The CX flight is the only nonstop option.

However, it appears every single seat is assigned on the seat map (via EF) and for this reason I'm unable to OLCI

There's plenty of availability in W and Y, but I'm not willing to accept a downgrade due to the length of flight - I would rather not fly, but I'd also like to know in advance to I can book another flight, not waste time at the airport etc.

What is likely to happene here? I'm Emerald if that makes a difference. Does CX have a certain order they downgrade passengers? Do they look for volunteers?