My mechanic told me that there was oil spillage originating from the diverter valve. I am struggling to understand what any oil was doing there in the first place as I assume the EGR is downstream?

Anyone had anything like this or any suggestions? I will pop it in to get sorted anyway but am still curious as my warranty is soon to expire.

I don't claim to know anything about the 2.0 TSI engines, but fundamentally the EGR has little to do with recirculating oil, and as you say it is further downstream. I would hazard a guess that the culprit is the CCV pipe on top of the engine which is venting oily vapour from the engine back into the inlet to burn it off (manufacturer's emissions law) and down the line some is being ejected from the DV. You'll also notice oily residue in your intercooler and pipework. Search here for Elephant hose mod and go from there.

Edited 17 February, 201313 yr by Ben90

OK I got this fixed. Replacement Turbo Air Divert Valve N249 fitted. Nice to get it in while still under warranty.