Are quarterly earnings reports first published on the SEC's website or issued in a press release? If they are first made available to the public in a press release then is there a website that is consistently among the first to post earnings reports when they are announced? Do any services send out email notifications?

It appears that most companies do not schedule the time of day that they will announce their earnings reports in advance. Does the exact time that the company will release their earnings report become available on the day of announcement, and how often does a company release their earnings report while the market is open?