What is shown as being op-up'd on OLCI cannot be guaranteed as the final word that you have been op-up'd as CX is still recalculating seat inventories. Your op'up can only be confirmed at the airport.
Basically as SL/GO members, you can be bumped off the list if somone else has a higher membership status as you and if they even checked in later. So you really have no reason to complain because an op-up is not a gurantee in any case.
So say you have been op-up'd and someone comes at the airport and wants to buy a F seat. Guess what, you can be downgraded even at the gate back to your original class you purchased your ticket!