You C is probably right that he is having a change of heart even a small one. But on the letter idea I don't know, I remember you saying he did not like it when you gave him pictures/updates of your cats. He may view the letter the same way and as a subtle way of pursuing.
But see for my H that would have been a good thing in hindsight but your situation and your H are entirely different. I certainly wouldn't rush into this just yet. Wait and see what others think about this.
