Hi there, our team released Nanominer 1.8.0 (You can find it here https://github.com/nanopool/nanominer/releases) this version have  Cortex support on AMD Radeon RX 570 16 GB cards. Average Hashrate about 1 G / s  on this moment this hashrate equal to  1.3 $ ~1.4 $ per day.
Please, note only the frostpool works normally with Cortex. The official cortexmint rejects a quarter of shares. Vulipuli does not allow to get connected. But this is the problem of Vulipuli, they are trying to solve it, but they only have green cards.