A turbo engine using a quart in 1200 miles is no big deal in my opinion. I have b230ft's that have used that amount of oil for over a 100,000 miles. Oil is cheap compared to a new turbo and a new turbo will most likely not bring your consumption down to zero anyway.

No reason to believe that that quart is all going through the turbo. Lots of oil in the turbo hoses? When was the last time they were actually cleaned out and then monitored for accumulation? Pull the drain plug on the intercooler and let it drain out and then do the same thing 5000 miles down the road.

Does it leak any oil? What may look like an insignificant amount on your garage floor can actually be quite a bit in 1000 miles on the road.

It is not unreasonable to think that some of your consumption is past the piston rings.

Your mechanic should have pulled the turbo hose and did a quick check of the shaft for axial and lateral "play". Saying the turbo will be due for a rebuild "in time" is a very safe bet.

Sleep well while looking at other possibilities besides your turbocharger.

Randy