We are installing Exchange 2010 in a 2003/2007 mixed mode environment. Currently, we have mail.ourcompany.com hosted on an F5 for webmail. We will create legacy.ourcompany.com on a new VIP for webmail on 2010, however what do we do about naming the internal CAS array? Do we create the array as legacy.ourcompany.com and then rename it when we perform the webmail cutover or just give it its own separate name like cas.ourcompany.com?