BO> one thing that puzzles me is why you you seem to thing that you've been cheated in some way.
You freely signed the contract knowing its content - since then the only difference I am aware of is that the company has increased your pay.
Whilst I fully accept your right to bargain to improve your pay and conditions, I fail to see that the company is in the wrong by maximising the use of its manpower resources as long as it stays within the legislation. So it's disruptive to your social life, work is inconvenient that way.
Fact is in Hong Kong a lot of people work a six day week with 12 days leave a year even in well qualified white collar jobs and you're doing a lot better than that.
I suspect that a lot of the rancour in CX derives from peoples expectations - i.e. that CX used to be famous in the industry for outstanding pay and conditions for pilots.
Well, things change, yours is not the only industry where pay and benefits have declined.
I suspect that most of CX pilots realise they're still on a pretty good deal and that is why the pilot body doesn't walk out en mass.
It is not the company's job to ensure you have a nice stable roster if they feel that doing so will reduce their ability to make money. Constantly changing rosters is the nature of the beast in civil aviation, and whilst pushing to improve that aspect in your company is fair enough, I suggest you be prepared to live with it.
At the end of the day if the lifestyle of an expat pilot in Hong Kong doesn't live up to your expectations no one is stopping you from heading off to where the grass is greener.
Having said all that I fully appreciate that if the company is making a lot of money the workforce is fully entitled to attempt to get a greater share of it for themselves. Just don't pretend it's some great crusade for justice, you're on a good deal, you want a better one - hai gam doh.