They are available thru one of five coordinators:
W5YI Group Inc
Western Carolina Amateur Radio Society/VEC Inc
W4VEC Volunteer Examiners Club of America
Laurel Amateur Radio Club Inc
It appears the 5 coordinators for the FCC are sharing the web page you cite: http://www.1x1callsigns.org
and that it contains THE authoritative database of US FCC specials callsigns.
Sounds like W7W had an issue this year.