If they are recruiting there should be a link allowing you to apply on the website. Like Qantas mainline recruitment, the link disappears when they aren’t recruiting so you have to check occasionally. No need to check everyday, as recruitment for these sorts of jobs stays open for a while. If you follow this forum you will also see it mentioned in the threads about the respective airline.
I understand the flying dream etc, but you have a good career with massive earning potential particularly if you are willing to do the hard yards in London/New York (get minted). Flying has some serious downsides from a health point of view. These include cosmic radiation, constant inhalation of petrochemical fumes, long periods of sitting, circadian flips including highly irregular wake times, the list goes on and on.
I just don’t think in your shoes, the return is there when you are already in a good career. I personally enjoy my job but wouldn’t recommend it to my children and looking back if I had my time over would have probably gone for something different.
My best mate is an investment banker and while his job also has some significant downsides the rewards have been there for the effort. Wishing you the best in your endeavours.