Fuses are in 32 bit words. There are 8 such words available for ODM usage, giving a total of 256 fuse bits. However, of those only one word is used for the anti

Fuses are in 32 bit words. There are 8 such words available for ODM usage, giving a total of 256 fuse bits. However, of those only one word is used for the anti-downgrade stuff. So that's just 32 firmware levels.