Bays 1 to 57, the four levels (M, N, P, Q), the last row on each level and the row where cover starts follow the MCG's published seating information. Each row of each bay is tested as one block, so seat numbers within a row are not separated.
The building itself is an estimate: tier heights, the roof line, even bay spacing and the position of bay 1 (placed at the eastern end, numbers running clockwise through south) are approximations, and the pitch is assumed to run north to south. Expect the real shade line to differ by a few rows. Cloud is not modelled, and session times move with weather and over rates.