Hi,

For example, Ornatrix Maya V3 is a major version, V4 is another major version. When you buy V3, you will get free updates for V3 until V4 comes out, at that point all development efforts are moved to V4, except for critical problems in the previous version. 

As stated in the documentation, you have several upgrade paths:

Free: If you bougth V3 six or less months before V4 is released.  

50% discount upgrade: If you don't apply for a free upgrade but you have a V3 license and you buy V4 within the first month of its release.

25% discount: For everyone with a license for the previous version. 

Jeordanis Figuereo (Product Designer. EPHERE Inc.)