You can request more information from Grayscale here.
https://grayscale.co/investors/?utm_medium=pr&utm_source=release&utm_campaign=2020_q1_BTC-open
***To begin with, you need to be an accredited investor so either a net worth greater than $1 million or income average the past 2 years greater than $200K.
***BTW, I think the minimum holding period was reduced to 6 months rather than 1 year.