What confuses me the most is that hex 0000000000000000000000000000000000000000 is 1111111111111111111114oLvT2 (27 characters) but hex 0000000000000000000000000000000000000001 is 11111111111111111111BZbvjr (26 characters).

20 zeroes in the beginning of the BTC address payoad results in an address of length 27.
19 zeroes in the beginning of the BTC address payload and then byte with decimal value of 1 results in an address of length 26.

But now all of sudden 17 zeroes in the beginning followed by the byte with value 1 results in an address of length 27 again.

What logic is there? It is said that the number of 1s in the beginning of the address depends on the number of zeroes in the beginning of the address payload but this dependency is no way trivial.