Re: WTF
To save yourself a bit of hassle in future should something similar happen again, and do the following:
Register your own domain (or use one you already have), and create a sub-domain that is a CNAME to your no-ip/dyndns etc domain. Set the TTL to an hour. That sub-domain is what you give out to your suppliers.
Next time the service goes tits up, simply register with another dynamic DNS provider, update your sub-domain, and within an hour service is restored.