2 whale addresses are converting MKR to SKY at a certain ratio, not unilateral destruction

On February 20th, according to Etherscan data, the address starting with 0x2b16 destroyed 17,262.99 MKR tokens 1 hour ago, exchanged for 416,711,896.8 SKY tokens at the official rate (1:2400).

The address starting with 0x06bF destroyed 20,933.76 MKR tokens 25 minutes ago, exchanged for 502,410,240 SKY tokens. Subsequently, 10 minutes ago, it destroyed another 15,001.38 MKR tokens, exchanged for 360,033,258 SKY tokens.