I bought a new Selmer Super Action 80 II alto that had acid leak. I was lucky enough to be in the US and so was the store. The store replaced it but shipped it back in a huge box without the case. They just wrapped the sax in bubble pack and use a box large enough for small person to fit into. Eventually got the case sent too.I appreciate the advise, will keep on monitoring it, it also arrived with a few scratches so I'll definitely opt on the partial refund.
If a partial refund is offered, that would seem fair. Or, maybe they know how to work with Yanagisawa so that you don't send it back to the UK but directly to some place closer. I personally don't look at acid leak as 'normal' though it does happen but it should be viewed as an exception, not the rule. But the partial refund is likely meant to offset the reduced resale value you'll probably incur if you or someone else decides to sell it.