The letter in entirety is a warning of potential legal action. That is the next action if the other party neither ceases or desists.

Maybe this is normal, but we're glorified animals trying to find justice out of a made up process. It's arbitrary, hence arbitration. Not a lawyer either. You probably know more terminology than I do; I just deal with them a lot :/

edit: I think it's a little strange to be placing judgements at this stage. We'll hear the facts if this goes to court. There's enough to know several are upset. Another consideration: by placing the numbers you're kind of trying to make their argument. Why? Let them.