Offsite Clients Updates

I had a curious question about the nature of how definition update work for clients that were originally installed from the management console (pushed) and then are off network for a fair amount of time (sales guys). Will the avast client go to check for the management server to get its updates first and when it does not find it automatically download the updates from the web?

I just want to make sure that these sales guys have update to date and working antivirus in the field. Let me know your thoughts.

The client first attempts to contact the AMS server for the update, and if it fails then downloads the updates from the internet. However, the netclients must check in to the AMS periodically for license verification (I believe at least once every 21 days) This can be done over a VPN connection though.