Insurers are no longer allowed to offer preferential terms to new customers.
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Ah, but how do you prove they ain't still bending the rules...
They are blatantly circumventing the rules. The FCA regulation has the giant loophole that it doesn't apply to price comparison sites. Insurance companies are still hiking their prices for loyal customers as they always did, but they offer better prices through the meerkats, the opera singer, etc.
My daughter accidentally failed to renew her policy with Aviva this year (she thought it would auto-renew but it didn't) She called them straight away but they refused to honour the lapsed renewal price. They also wouldn't give her a new quote but told her to go to a comparison site, which she did. The quote from Aviva on GoCompare was cheaper than the renewal, but there were several cheaper still so she went with one of them.