I have good friends working there and the picture is the following:
Yes you can choose the 11-days-off contract option. But 11 days off means you might not must have 11 days off at home. They try to organize a reverse-roaster from your overseas base, but if they cannot in a specific month you will commute to/from China as dead head crew on your days off, so it‘ll be just 8-9days off at home, so 3days less than advertised. Plan about +50% reverse scheduling, subject to change in both directions.
The following is true for most chinese airlines, not specific to HNA I think:
Plan to live in a permanent state of uncertainty. Noone knows how long your training takes, e.g. 2-3month is absolutely unrealistic, the madness of bureaucracy in CAAC is huge. Till being released as a solo-captain on a long haul (or better say mixed with domestic) fleet like B787 at HNA expect around +1year! that means in between you gonna work as a cruise relief captain (F10).
Everything(!) you are saying or doing is supervised and someone will spy on you. I am not saying that your chinese colleagues won‘t be nice to you, but don‘t expect to go on a long haul trip and „have a fun time with your mates“ there...
Noone knows if you gonna pass if you gonna pass the multiple sim checks during your training. The training department is not the recruitment department. If there should arise any problems during that period or during line training you will hardly be able to sort this out as many trainer’s ability to speak english will be very limited. If in doubt they just kick you out, contract terminated.
If you fail the CAAC medical (2x/year >40yrs), no pay. fail permanently, contract terminated.
I am not saying that this will happen to you, but let‘s say 1out of 10 guys is getting into serious trouble during their time on contract.
Finally the good thing: the money is really good, even as the above mentioned cruise captain you will receive the full capt salary, plus variable bonuses, plus overtime. On „11 days off“ you can easily make +300k net USD/yr! But there‘s a wise saying regarding every contractor job: you are only as good as your last paycheck;-) Can be over tomorrow or can work out for the next ten years, noone knows:-)