There's two factors to consider. There is the initial grant, and equity refreshers.
Normally, you'll get an initial grant when you join. The size of this grant will be decided based on its dollar value at the time of issue (ie scenario 1).
The grant will then vest on a schedule over the next 3-4 years, and the proceeds you earn depend on the price at which you sell your stock when it vests.
If you perform well and the company wants to keep you around, they may issue a refresher every year. This is where they issue you with additional RSUs on top of what you have, and this stock has its own vesting schedule; sometimes part of it will vest immediately, so in that case it will be like scenario 2.
The size of your refresher will also be determined by its value at the time of issue.
Normally, you'll get an initial grant when you join. The size of this grant will be decided based on its dollar value at the time of issue (ie scenario 1).
The grant will then vest on a schedule over the next 3-4 years, and the proceeds you earn depend on the price at which you sell your stock when it vests.
If you perform well and the company wants to keep you around, they may issue a refresher every year. This is where they issue you with additional RSUs on top of what you have, and this stock has its own vesting schedule; sometimes part of it will vest immediately, so in that case it will be like scenario 2.
The size of your refresher will also be determined by its value at the time of issue.