The above FAQ when downloaded says it is FAQ May 2017 this is over a year old, did it take them a year from doing it to releasing it? This is very odd are there other FAQ's done for other games still to be released.

Why are they holding back their FAQ's?

The FAQ, v.1.3, is from May 2018 but they've forgotten to change the date. FFG did the same with the January FAQ. It's just a typo. They realised this FAQ on the last or close to last day of May, hence a May rather than June date.