Presumably the same time they come out for anyone else selected to participate in Alpha 6. The deadline for sending the applications in has passed. So now Bossa has to sift through them all and decide if they meet the criteria they are looking for. That takes time. I wouldn’t expect it to happen this week (and certainly not over the weekend).
Being contacted and getting the key are different matters. If you’re contacted today, then it’ll probably just be a note informing you that you were accepted into the playtest. The playtest itself doesn’t yet have a date.