Thanks to all who replied. Yes I fitted the tyres when the original Pirellis were due for replacement. I'm diligent with the pressures as recommended by Porsche ( and pirelli). Both rear tyres are worn evenly across the face of the tyre so I assume the alignments is good .
I've had Pirellis on other vehicles without problem which is one of the reasons I was keen to fit them again. I've written a rather terse email to Mr. Pirelli here in Australia - the reply I received was as expected biased towards my driving technique and conditions. I have since replied with the "dot" information off the tyres as requested in an effort to track the tyres and 'batch' them. I have since spoken at length to the workshop manager of my Porsche Dealer who told me that he had never experienced this sort of premature wear on a car that he knows is not driven hard. He has suggested fitting Continentals (?) I'm still unsure what to go with at this stage.
Pete from OZ
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