Are all these letters going to generate a book in the end?

I don't have one planned! Though it was reading Gwen Raverat's Period Piece, and spotting some of my relatives there in a walk-on part, that put the idea of this series in my head. I'm getting near the end of my highlights from Butler Verses and Records now, but my lackadaisical researches have led me in some interesting directions, and as long as I keep kicking up rubies I'll probably keep digging.