I am mining Monero coin with the both versions on the same rig . 8.6 and 8.7 . Both are keeping rr my rig after a few minutes ... All gpus in this rig are rx570 4GB . i have another rig with rx580 8G and your miner doesnt restart ... Do you know why i have this issues ? Thanks .
rr = restart ?

SRB should work fine with all Polaris cards, so rx580 8g should work too.
Maybe you can upload your log file from both rigs somewhere and share, that way i can get more info on what is happening.