July 10, 2018 from 1 to 1:45 p.m. (EST). During this teleconference, USCIS officials will provide an overview of the information provided in the Federal Register notice, including re-registration and employment authorization document (EAD) application procedures. USCIS officials will also respond to your questions.
To Join the Teleconference: On July 10, use to call in 10 to 15 minutes early.
Toll-Free (inside the U.S.): 888-995-9858
Toll (outside the U.S.): 1-517-308-9166
Passcode (for both numbers): 4141645
Source: http://immigration-law.com