We understand your frustrations with this bug and its impact on gameplay, and it is right at the top of the list of things we're looking into. Unfortunately, I still don't have any status change for you - we are still looking into it, but there is currently no ETA for a fix.
As soon as I hear anything, I will let you all know.
In 2.8, we are making some changes to how the spam filter handles /say messages to the opposite faction, so this should clear up the issues you're seeing. If you still continue to have problems after 2.8, please let me know so I can pass it along.