This reference suggests, among other things, that the 18 MHz and 25 MHz band
was added. No date given.

http://www.qsl.net/vu2ngb/freq~band.html

This site seems to be more current. 10.1 MHz is not mentioned.
http://hamradioindia.com/HRI-RULES/IWTA.htm

The chances this December of more than a few of us in the north-central part
of NA working VU4 is small. In view of the earthquake, all of this is moot.

73 Mac N8TT
J. Mc Laughlin; Michigan U.S.A.