The craziest thing for me is when you you're given Jump seat status one by the Captain of the Aircraft no less, then the ground staff realize that there is an economy seat available after everyone has checked in and then you are told to decamp to the economy section
Was made to wait until 45 mins before departure before I got a boarding card, despite having J1. Got to boarding gate to be given an economy seat. I pointed out to the ticket lady I had J1 and would prefer that seat, she looked and me and told me that I must take the economy seat and not J1 as that is the rules and I should know better than to ask.
I'm not apologizing for CX staff travel, but the rules do say that if the flight is expected to depart with passenger seats available, then no jumpseat boarding cards should be allocated to ANY [staff] passengers. They also say that all [staff] passengers are required to standby until 40 minutes prior to departure, and that no early issuance of boarding passes for Jumpseat pax will be entertained. It's all in OPM-A 14.14.
While there might be a J class seat allocated for cockpit crew rest on long haul 744 flights, you'll only get to use it if you are issued with a jumpseat boarding pass, and then only if the operating crew aren't using the seat. If there are empty seats in economy that's where you'll be sitting.