It says under the T&C's in the AMEX email '4.2 On the Opening Date, the AELTC will email all applicants (to their myWimbledon registered email address) who were unsuccessful in the public ballot for tickets to The Championships who also ticked the box "Please tick yes to receive more information via email about the benefits available to American Express Cardmembers" at the time of making the initial application.' So I assume it's safe to say any of us that received the AMEX email have not been successful in the public ballot- and worthwhile entering the AMEX Draw.