BACKFLIP — first eight-cell route
Trace BACKFLIP through these cells: 1 at row 4, column 3; 2 at row 5, column 3; 3 at row 5, column 2; 4 at row 4, column 2; 5 at row 4, column 1; 6 at row 3, column 1; 7 at row 3, column 2; 8 at row 2, column 2. Reading the letters in that order gives B → A → C → K → F → L → I → P, with every step moving to an orthogonally adjacent cell.
The movement sequence is down, left, up, left, up, right, and up. Direction changes after each of the seven moves, so the route has six turns and seven straight segments. It spans four rows and three columns, visits two edge cells, and does not visit a corner. The starting cell has four open orthogonal neighbors, while the ending cell has two. Once this path is assigned, eight cells are covered and 16 remain.