What's the procedure of getting Engagement mining approval??

Actually we're interested in creating a new board but I don't have much knowledge about all these things that How will we get Engagement mining approval? 

What are the requirements that you need to fulfill before approval? 

After how many days you can request for Engagement mining? 

And After how many days you'll get approval?? 

Basic requirement : 

The only thing I know is we need 10 posts from unique members to get approval but for how many days we need to be consistent with these numbers?? 

What if you are continuously getting 10 posts from unique members and than one day you can't complete your target, Will this effect badly?? 

Once you get approval after that if you're not matching their requirements will bbs take cpm back from you ? 

If anyone of you have detailed post on this topic, kindly share it's link with me otherwise help me in comments section

Thankyou