My understanding is that it was signed before this letter was sent. It doesn't matter when the letter was received; you met with him beforehand. Whether it's signed or not is a detail. Say it was about to be signed. I'll give you the point, even though you're wrong. Say it's about to be signed but it hasn't been. Why didn't you say “Wait a minute. Why on earth would I do that?”
On April 3rd, 2008. See this statement in context.