According to an announcement on Paladins official website, Paladins is set to kick off the Closed Beta on the 17th of November. The initial server for both Europe and North America is expected to run from noon to midnight US Eastern (18:00 to 06:00 CET).
The first closed beta codes will be distributed by mail to the e-mail address you entered when you registered for the beta with your guaranteed early access code. The codes will be sent out on the 16th of November, so make sure you check your inbox on that day. If you cannot find the e-mail containing your code; don't panic. It might just be in your spam folder.