Host Gator changing my IP address for VPS. What do I do for Multisite domain mapping?

Hostgator migrated my VPS to a new server and now I'll have a new IP address. I'm worried that it's going to be a nightmare to update the 'A' address for all my client's site's domains. Is there any way to prevent this kind of thing in the future? Is this the only way to go about this? I'm really worried about if they do this again in the future when I have hundreds of domains to update.