New to the game with a few questions

[Nynzy]

I apologize in advance for asking some of these - as I'm not entirely sure how to find the FAQs i've seen people talk about, or how to properly search the forums.

When do units change at various islands and buildings? Like the starting place just happened to get more inquisitors and even paladins after just having priests for a long time, aside from that 'scanner thing' is there another way to know without traveling all over the world?

If there is indeed a walkthrough or FAQ or something for this game, could someone please direct me to it as well?

Sorry for the noob questions, and thanks for any help.