Due to Apple's yearly macOS upgrade cycle, it may happen your license doesn't support the new OS. With Hedge's commitment to release a compatible update on the day of Apple's release, each macOS release tends to cost us a lot of work. The amount differs each year. Based on how much effort it requires, we decide to release support for a new macOS either as a minor or major update. If it's the latter, you might need to extend your license. Make sure your license is valid for the latest macOS before making the jump to the latest macOS, and factor in the cost of extending your license. Also, keep in mind that when buying a new Mac, you cannot downgrade macOS to a version that is compatible with your licenses.