I liked the cropped image so much, I grabbed a hand saw and cut the top and bottom off the original!
But I did cut and prime myself a new board and created a whole new painting using the cropped horizontal format. I've made an animation of the stages and will post the final image as soon as I can get a properly lit photo. The animation image is about 2Mb so it might take a little while to load.
(Summer Shadows animated stages. © Andy Dolphin)
To do this painting, I cropped the original photo of the scene and painted from that without referring to the previous painting at all. I wanted this to be a painting in its own right and not just a copy of the previous painting. Now that it's done, I think it's turned out faithful to the first painting but quite different in the detail.