What's the point? The addresses TWC assigns are extremely stable in my experience. Are you trying to run a public-facing DNS server or do you have some other need to hard-code IP addresses?
why are they hosting services on their dynamically addressed business line? everyone offers static addressing on business lines. it's a completely rip off; and conveniently makes the proper route -- colocation, a dedicated server, "the cloud" -- more financially sound.
Before you suggest DDNS, for some companies, the length of unavailability between a changed IP and the DDNS client noticing and updating can be fatal.