And to anyone still looking for a solution in the meantime, I found this app. It's unfortunate we have to pay an additional $50/month to prevent something that should not be an issue in the first place, but at least it works! https://apps.shopify.com...

Hi John, Having the standard functionality be to change the default address every time there's a new order completely defeats the purpose of a default address. This has been a known issue for at least 4 years now. Is there a fix to this?  It truly ba...