Special min difficulty rule for testnet I heard about this "special difficulty rule" for testnet, which allows blocks with timestamp 20 min later than the last block to have the min difficulty target.

So does it mean that the miners can simply declare that their block has such timestamp without actually waiting for 20 minutes?
It seems like that's the case... I mined a min-difficulty block only 13 min after the previous block(only for testnet).