After looking at the VOA, I guess M1 10w40 is the way to go with it's lower Ca and higher Mg. This is a turbo DI engine after all. Thankfully it's significantly less expensive than the Castrol 10w40HM.
Car is running fine but it needs the timing chain system replaced (tensioner is at max extension) and I'll probably do the PCV system myself in the near future. Not burning much oil but want to keep it that way. It's a class action and TSB for Audi anyway for oil consumption and timing chain system. Apparently a lot of these engines suffered from poor quality cylinder rings from a vendor and poorly designed timing chain tensioners pre-2014.
I would stick with Castrol 0W40. You will not gain anything with HM oil.
I changed tensioner at 68k preventively and installed updated one.
Reengineered piston rings, PCV are mid-2012 as well as chain tensioner (this affects 3.0T engines too).
I would change tensioner ASAP, and stick to Castrol 0W40. PCV might alleviate some of your issues as that is first culprit.
By the way, what oil are you using now?