Emails are sent each Friday for six weeks starting on 17th July. You can catch up on previous emails by visiting the Challenge page where there is a link to each email (added there after the weekly email is sent).
After registering did you receive the Opt-in Confirmation email and click on the Confirm button? Check your Spam or Junk folder for the Opt-in Confirmation email and click the confirmation button in the email. If you didn’t receive that please send us an email via our contact page.