That’s quite a bit of consumption. If you’re not blowing blue smoke, there’s got to be a leak somewhere. Just like the OP, oil either burns out the exhaust, or drips somewhere.
I have an early-mid build 18 and just about 3k since last oil change and still pretty much in the middle of the dipstick. 13k miles total to this point.
I’m not familiar with the valve cover TSB, but could it be a small slow leak dripping onto the manifold and burning off? When the truck is warm/hot do you have a slight burning oil smell under hood?
It’s got to go somewhere?
I don’t see any leaks nor smell any oil burning. I haven’t seen any blue smoke but I haven’t been looking.