EDNS(0) all EDNS queries have timeout and there was a response to the plain DNS query
EDNS(1) only the two EDNS version 1 queries timeout
EDNS(1) + FLAGS the two EDNS version 1 queries timeout as well as the unknown EDNS flags query
2014-10-12 - 2014-10-15: Domaincontrol removed the firewall blocking EDNS version 1 and EDNS flags.