[Dancake]

It is quite difficult to get a good look at the pipes, but you need to see if they have been installed correctly. Ring the mechanic that done the work and ask if the turbo return pipe was replaced along with the turbo. Reusing the old pipe is bad practice, as a build up of varnish in the pipe can restrict oil flow. This causes the oil to back up on itself, and it has nowhere to go but past the turbo seals. Refitting a turbo incorrectly can cause the symptoms you describe. The new turbo is probably fine, but the pipework needs checked.

Also have a look at your air filter. When was it last changed? A blocked or heavily restricted air filter can cause oil leaks at the turbo.