Cathay Pacific use either 3 or 4 crew on LH/ULH patterns.
Duty time & departure time within the 'local night' defines the requirement for adding a 3rd pilot but how many timezones you cross can add the 4th pilot.
<5hr timezone change....3 pilots
>5hr timezone change....4 pilots
Some 11hr flights routing Nth/Sth will therefore have 3 crew. Whereas an11hr East/West flight will need 4.