AT&T flapped in Washington?

Hi all, Anyone have any information on the 20 minute (or so) flap that appears to have occured in Washington between AT&T and the rest of the world? We saw a complete outage of connectivity to several APIs at a few parnters who happen to all be behind AT&T. Although in BGP the routes were still being advertised across this peering from AT&T to the world, traffic just died at the washington peering with AT&T irrespective of which path we took. (3 different transits here). Just curious. Thanks, Leland