Fiat 500 servicing

The dealer my wife bought her 59-plate Fiat 500 1.2 lounge from is insisting that if the car is not serviced after 1 year her warranty is invalid. The information in her service schedule says it should be serviced at 18000 miles and does not state an "or at 1yr, whichever comes first" timescale, the car has so far covered 11000 miles. I have read your thoughts on servicing/oil changes but can a dealer legally demand that a car is serviced before the manufacturer's state that the service is due?
It needs a service every 18k miles or every 12 months whichever comes first. Certainly needs an oil and filter change after 11,000 miles.
Answered by Honest John on

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