Review the latest information on the SMS signup.
If you do not receive the text/sms updates that go out you may have previously signed up using email but omitted your mobile number. If you know you signed up and are not receiving the messages you may need to use the verification signup instead.
New Signups: Signup using this form here.
Verification Re-Signup: If you know you signed up and are not receiving the messages you may need to use the verification signup instead.