I have always played the 7th. I believe the "Change" refers to the fact that errata was released (probably through the General magazine) and then later changed again to read the 7th.
Shoot! Now I have to go downstairs and check for sure!
In The General Vol 17 No 6, it stated they could move on June 6 and it was later clarified that it had to wait until June 7 (in Volume 19 No 2).
Thanks Robert. Does Vol 17 No 6 have that "V.A." note and if so, does it state that it is for the Campaign game?