Thanks to Grishnar over at theBrasse.com for bringing this to everyone’s attention.
At some point today you’ll be able to enter your beta and headstart codes into the Mythic Beta Center. There’s really no rush if you pre-ordered the CE, but the first 50,000 ‘standard’ pre-orders to enter their codes will get an invite into the upcoming Preview Weekend. So keep checking! (I just checked at 8:15 am ET and my Head Start code was still flagged as ‘invalid’).
More details from the source: