questions before purchase

Hi All,

Just a quick few things before we purchase this software.

We are a managed services company, we are constantly adding/changing/removing routers and interfaces on those routers. For example, one of our clients is a construction company, and they have aprox 12 sites that move every 6 months. When they move, the router is shipped back to us, blown away and re-configured for the new site they setup at.

What we really need to know, is how netflow handles this type of thing. If we purchase a 250 interface license for Netflow Pro, can we delete the router from the old construction site, and then add it back in when they are at the new location? Can this be done without wasting any licenses?

Or once the interfaces on those routers have been communicated to the netflow server, it is gone forever?

Thanks