Dang that bird looks like a meteor lol! Sorry man couldnt resist.
Looks like a classic case of burnt sugar to my eyes. Try ditching the sugar altogether and use a simple SPOG rub instead and keep your temps as is and you'll be good to go.
UDS'-55&16, Akorn, Bar-B-Q Kettle, Drum Grill, miniWSM, cobweb-covered gasser. I'm JD.