Reply To: 9b
I’ve just cracked 9B so can provide some clues (Harry can remove parts as necessary)
To start, I would use a text editor or word to reverse the letters in the cipher text.
After that stage, I would remove all the spaces and then find the total length of the text and find factors of it. The keyword length is larger than you’d expect (so more than 10). Based on that assumption, I would arrange the letters in rows and columns and have the end of the last row rearranged so that it says “ABRAHAM WOODHULL”. Rearranging the first few columns should be fairly easy from there on.