WebStorm Version 2.1.4 to Version 3.0 upgrade policy

Hello,

I've been testing WebStrom and I like the IDE very much.
The sad thing is that my evaluation period is ending soon.... but I've decided to buy
a license.

Now my questions are:

What if I buy a license this or next week and then you release Version 3.0?
Will I need to buy an upgrade?
Or.. should I wait until V. 3.0 is out to buy a license?

Thank you!!