generally, all license questions should be addressed to Sales using the Contact form.
Previously we charged for upgrades to new major versions (for example 3 to 4 or 4 to 5). The customer had to purchase an new license even though we have never checked if the customer has done so. Minor upgrades has been free.
Instead of purchase a whole new license we implemented the Maintenance pack. This gives you any update that is released within a year. The Maintenance pack is valid for one year and one year is $47 per server. For a site license this renewal is $297.
We think this is a better option because the user can choose if he/she wants the new functionality and if it is worth upgrading and also forces us to constantly deliver new functionality.
The Maintenance pack also gives priority support. You can read more about the Maintenance pack here: http://www.visualcron.com/Maintenance.aspx
The Maintenance pack can be ordered here: http://www.visualcron.com/Order.aspx
You can view information about you current license here: http://www.visualcron.com/ActivationInfo.aspx