Originally Posted by
danger
Who issues your ticket has no impact on seat preferences. Each individual airline has its own policy. At a guess, oneworld Sapphire would allow you very good (and free) selections on most oneworld carriers, certainly in premium cabins anyway.
JL is one that I know holds back a lot of seats for Emeralds in business. But they'd all be available at OLCI. I've rarely not been able to do OLCI with JL even when they should be checking visas (like one way to China for example).