I suppose ATPL theories being the 'threshold' makes sense as it's the point at which you start the transition from private to commercial on the modular route, and all the integrated courses start with ATPL learning.
Thanks average and Alex - I'll get my membership in...
Reason I'm joining is one of my instructors went through training, did his TR with Eastern and the week before he was due to start on the line, he did something funny to his back getting out of the sim. Didn't fly for 3 years and lost his Class 1. Luckily he had BALPA training insurance and received a substantial payout - enough to fund his 3 years off + medical costs. And of course the legal assistance if you should ever be in an unfortunate situation...