*""When you arbitrarily change an agreement (dishonest)"

To which agreement are you referring - we have a merchants guidelines document that we change from time to time to reflect the latest policy guidelines."*

4 months ago it didn't matter where else you worked online and didn't state this on the upload page, and still doesn't. And then one morning it did matter. Your sparsley worded agreement on the upload page didn't say they couldn't work elsewhere. It only stipulates the exclusivity of the product. You added to the "agreement" and implemented it in hours. And this implies that you made a change to a feature that was previously implied and accessible to all merchants. That is not what those merchants agreed to when they uploaded. And that was dishonest.
The merchant forum is implied and is automatically accessible when a first product is accepted. It may not say that it's included in the agreement but it doesn't say it's not either. It doesn't stipulate situations that would make one merchants access different than anothers.

...... Kendra