Got the update about the deadlines for LEvel 3 being changed to 20th July for sign up and thought it was strange alright! So, I checked the CFA website and they do have caveat underneath the deadlines for registrations saying:
*Candidates who sat for the May exam and candidates who have been granted a deferral to the November exam will be able to register for the November exam after the 20 July deadline. If you qualify for this later deadline, further information will be sent to you by email in early July.
Hope this helps!