There shouldn't be any left in the finished beer, unless the yeast produced it. During oxygenation all the remaining sulfite should get used up before fermentation.I don't know about temp dependence, I hope not.
I'm just saying that the sulfite should be gone at the end of oxygenation, you might have other sulfur compounds in there (sulfate for example) that are detectable though. If you don't use up the sulfite with oxygenation, then I think you are more likely to have the yeast interact with it and produce unpleasant sulfur compounds. I believe this is how I have ended up with a couple fart beers.
Does using campden tablets to remover chlorine/chloramine factor in the SMB dosage rates?