.... which means that your engine is not being properly protected by the oil and is wearing out rapidly.
Do understand that these high-miles service intervals are designed for the new car user on a fleet doing lots of (motorway) driving. Fleets are only interested in costs, not longevity.
As Andy has said, its cheaper to change the oil more frequently and your engine will last like its supposed to.
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1994 850 2.0 bought at 32,000 miles used daily now 45,000. Still like a nearly-new car 
2004 filthy polluting diesel VW
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