Actually looking at simulationcraft''s sample sequence for T22 destruction warlock, except during bloodlust/grimoire of supremacy, almost every chaosbolt is preceded by a conflag
if buff[WD.Backdraft].remains < 2 and SoulShards >= 2 and currentSpell ~= WD.ChaosBolt then
the problem is this kicks off even if you don't have backdraft as a buff, meaning Chaos bolt is being cast at 2 shards no matter what. I modified the if statement to the following
if buff[WD.Backdraft].remains >= 2 and SoulShards >= 2 then
doing this does 2 things. It prioritizes Backdrafts to be on Chaos bolts and also, like during Infernal uptime, it will allow you to cast 2 Chaosbolts in a row if you have backdraft.