ControlDraw software is intended to improve continuously. There are frequent updates and these are made available to all licensed users. The updates are made available when a new feature has been added or improved - these releases are rolled up with bug fixes.
Reverse and forward compatibility between versions and models is maintained over a 1 year reverse period and 3 year forward. That means that a model can be edited with a 1 year old version of the software and with the current version of the software in 3 years time.
Please note however that an older version of the software will not support newer features, and a model that has been created with a newer version and then edited with an old version may not retain settings that were created with a newer version.
At some point it may be that a new version is released that does not maintain reverse compatibility, so Previous versions of the software may not work with models edited with the new version.
If that happens:
ControlDraw will inform users in advance, typically via statements on the Web site.
ControlDraw will continue to maintain the last version for licensed customers.
In this case maintain means fix bugs, and this will only be done for 15 months after the release of the new version
See also complete update