Policy Based Routing using Application Control

Hello Everyone. 

I have a challenge from a client of mine. He has two internet connections and we want to route traffic to Office365 out on one connection and traffic to everything else out of the other connection (default route).

I know that by using destination IPs for Office365 I can send traffic in the second connection with an static route. 

I am afraid of MS changing IPs and breaking my route and policies. 

Is there any other way to identify traffic going to Office365 in a policy and route it base on PBR?

Is anybody doing this out there for Office365?

Thanks in advance

Jack.