The label Attack The Music used to have a custom domain set up for their Bandcamp page at https://shop.attackthemusic.com, and many releases such as EmoCosine’s Shake The Future! EP have been created with URL relationships pointing to this domain as if it were Bandcamp (since, by all means, it was).
Unfortunately, the label seems to have messed with their DNS/webserver configuration, and https://shop.attackthemusic.com/<path> now redirects to https://attackthemusic.com/shop/<path>, which is not Bandcamp.
If anyone has a bot set up, or you personally have a lot of time on your hands, please consider editing all former Bandcamp custom domain Attack The Music URL relationships to their official Bandcamp equivalents, which can be found at https://attackthemusic.bandcamp.com/<path> — yes, all you have to do is change the domain.
You can find all relationships with the API:
I have personally been adding both the custom domain and the official Bandcamp domain URLs for releases of which that applies in fear of something like this happening. (as in, I’ve done it like, twice.)
Thus, I have a style proposal. I believe it would be a good idea to require the official Bandcamp domain to be used in relationship URLs, optionally in place of any potential custom ones. According to the Bandcamp help article linked above, the official domain (<artist/label>.bandcamp.com) should automatically redirect to the custom one, but this is “currently” broken (has been for the last two years apparently), and custom ones redirect to the official one (if the DNS records aren’t misconfigured).
Style proposal ticket: https://tickets.metabrainz.org/browse/STYLE-2798