This was all worked out on PowerPoint before hand. I started with a 7 lots of 5x5 grids where all the walls were present. Then put Tanith in the middle of the year 3000. With that layout, the only square she could access was the middle one. After that I removed a single wall on one of the years allowing her to access two spaces on every year. Then it was just a case of expanding that idea until all the spaces were accessible somehow.