The early signing date and all information related to it can be found at the website for the National Letter of Intent (link below). This year the period for baseball is November 14 - 21.
When you block a person, they can no longer invite you to a private message or post to your profile wall. Replies and comments they make will be collapsed/hidden by default. Finally, you'll never receive email notifications about content they create or likes they designate for your content.
Note: if you proceed, you will no longer be following .