its procedurally generated, so its simply the amount of digits in an unsigned int in the seed
but also, there's a limit in the fact that an 8x8 grid only has 16777216 combos, and most of those are useless (mostly filled in, checkboard)
yes! check the dev blog posted https://frinkygames.itch.io/scp-frontrunners-prototype/devlog/290566/steam-relea...