I have not been directly affected by the issue. But IIRC, Honda Europe/UK only slowly, and reluctantly moved towards accepting liability for the fault,under warranty and eventually as a recall. And only then because of increasing pressure from consumer groups such as this forum who knew Honda had already accepted liability ,and doing recalls, in other countries.
During this period some customers were still charged for the work, but Honda gradually became more amenable to price reductions as 'a goodwill gesture', and possibly made refunds or partial refunds for sums already paid. At least to those customers who knew enough to complain, with effective arguments.
If I had paid for repairs I would expect a full refund from Honda ,and would take them to the 'small claims' court if necessary. Now they accept its a free recall issue I dont think they have much of a defence for having previously charged customers for the same work.
Be aware that initially you may be dealing with "Honda Administration" who are in reality an independent business solutions company , TWG Services Ltd . Their business model is to save Honda money by refusing as many complaints and claims as possible ,which may never reach Honda. Dont accept an initial rejection. Persevere to ensure its considered by Honda themselves. Its their reputation at risk, not TWG Ltd.
I would recommend keeping any communication with Honda, dealerships etc as polite and as reasonable as possible. And maybe give them a chance to do the right thing before threatening court action. Indeed you need to show you have tried to settle the claim with them before taking any court action. . Keep a record of any communication sent or received as it may need to be submitted as evidence to the court.
https://www.gov.uk/make-court-claim-for-money