sorry, i'm not such familiar with turbo issues,

but for n/a i'd say: blue smoke...
-... when start up, after a throttle release+floor it => valve seal or guides,(or thin valve/s),
-...after idling+floor it => piston rings.

you may also have some issues with the crankcase ventilation...
this might be detected running it, in normal condition, with the crankcase ventilation hoses disconnected for a while (not too much, to not to soil the engine bay with oil vapours).

but it could be either a badly overhauled turbo. even good technicians do mistakes...

i apologize for my bad english too.
hope it helps you to find out what it is...
(i'm curious too) keep us posted on this one.