American Express Membership Rewards - Targeted Amex Business Gold Rewards Card: 50K for $5,000 spend by Nov 9 2012

I have received a targeted offer in the mail, first year annual fee waived. The fine print says:

"Welcome bonus offer not available to applicants who have had this product or any other Business Gold, Green or Platinum Card account within the last 12 months".

I do have the old Gold business card (without 3x points on airfare, 2x points on....) but I can cancel that one at any time because it has been almost a year and the annual fee is approaching. Will I have to wait 12 months after I cancel this card to apply for another business gold card?

And how about Platinum business credit cards (not charge cards), such as the no annual fee Amex Simplycash? Will that card preclude me from earning welcome bonuses in the future?

There is some discussion of the new terms in this thread about a similar offer:

http://www.flyertalk.com/forum/american-express-membership-rewards/1358602-gold-business-75k-w-10k-spend-not-targeted-expires-6-26-12-a.html

The literal reading to the terms would mean that you would not be eligible to earn a bonus on a business green, gold or platinum card until 12 months after you cancel your current business gold, but some CSR's have indicated that it only means that you cannot have opened a new business charge card account within the past year.

The business credit card should be irrelevant.