Surely if their system isn't configured correctly to limit the amount sold during this presale (1 box) then this shouldn't be your issue and you then have your membership cancelled?
A simple refund of the 9 extra boxes and a "we apologise for letting you order 9 more boxes than you should have" would have been more appropriate?
If they have cancelled your membership over something that technically is their fault it is pretty poor.
I would certainly call them and plead your case.