If I delete all my listings on the international marketplaces (except UK) and re-enable the Build International Listings afterwards so that new listings are created on the international sites again... would there be any downsides? Obviously I will temporarily lose some sales until the listings have all been created again. Would it upset any algorithm?

We've recently used the Build International Listings tool to add listings to Amazon Ireland in preparation for its launch. However, we're now seeing multiple offers appear in the UK for many of our listings, and the one winning the buybox appears unpurchasable to most UK postcodes.

Despite our best efforts we've not been able to resolve this. Has anyone seen something similar?

There is no way to delete the connection, although I have managed to delete the listings (which also removed them from Amazon UK!)

After clicking the "opt out" link I am taken to a page to build a connection - with no opt out options on there.