ADNM installs the database when you install it. Then, it automatically downloads updates and pushes them out to the clients. You can do that with my following explanation...
Look at your "Updating Tasks" in your ADNM console. You should have an "Update VPS" task already. Schedule it to run every day, at an appropriate time (meaning, a time when it would be least obtrusive to run the update on all of your computers ie. early morning, lunch, or after business hours) and when you know that your computers are on.
Then, you should also create another task that runs at least once a week that "updates everything." Have it do a program update, which will update the client avast versions, and the VPS as well.
Then, you just let it run. The only time you have to touch it is when new computers are added to the network and you have to push installs to them, or if you need to modify a setting or two.