My experience with the local trading standards was not a good one.....I wound up taking direct action myself after they messed me around for several months and hid behind the "data protection" excuses.
Small claims court, Defendant, (as is his right) had case hearing moved to his local court.
Won my case, maximum compensation plus the plaint fee plus an expert witness report....on top of that, defendant had been using a solicitor to try to intimidate me into backing off.....those costs are NOT allowable, so I sent lots of letters to his solicitor.
sweet victory.
If I had a crystal ball, I'd say a company that was extremely tardy with refunds,would probably be short of cash and waiting to get enough deposits in to use to refund to the loudest shouters.......a bit like Bernie Madoff ,really.
Send a letter to company's registered office (email would probably be OK) giving notice that unless refund is IN YOUR ACCOUNT within 7 days, you will issue proceedings.......as soon as you issue a Plaint (summons) the defendant is answerable to the Court (even if the cheque really was in the post).... if he loses ....which he undoubtedly would, he'd
still owe the cost of the plaint and certain other limited costs.
Just go ahead and act before the company folds and there's nothing left for you!