Yes, it is confusing, @Laura1421 . It's not you.
So, the 100 days or 10 stays are over a year. Not over a quarter. But superhost is given quarterly. If you cancel in the quarter, you lose it.
The overall rating is over the year. So your 4.87 is for all the years you have been hosting, but your 4.7 is for the past year, and that's what counts.