Do you see oil smoke from the oil fill tube while the motor is running?
If your turbo seals were eating oil, you'd have signs from the exhaust.
Why are you using a 10w30 oil? This will attribute to some oil loss.
The issue here is not so much lack of boost, but oil consumption. Rule out the big before the little. Since you have an AP, do a data log and that will give a LARGE idea of what is wrong.
My guess is dead/dying motor.