Dump valve issue after clutch change ?
 

Got a 54 plate wrx blob just had a clutch a exeedy and only picked it up this morning all in including part was 520, I used take my bmw to these all the time so I'm a repeat customer, the issue was it was slipping when I got into the turbo area it just revved up and no power but now clutch side is fine when I change gear in first and second at high rpm the dump valve sounds Grindy or a dragged sound but it's fine in 3rd 4th 5th etc any help would be appreciated

Maybe the spring inside the dump valve is on it's way out .....