about mining pools backing BU, the list is sure longer: gbminers, btc.top, viabtc, bitcoin.com, canoepool, bitclub and of course AntPool.
Just to elaborate further, antpool is dedicating 75% of its hashrate to BU, and bitclub being in that list is an error; I know doin.dance is listing them but it's wrong. They're definitely advertising segwit only.