yes..goto my.astaro.com..if you ahve not registered do so..then get your license key from your v4 webadmin..and put it into the license key area of my.astaro.com and it will convert it for you.
Licensing is for an instance, not for which version. As long as you're not running both at once in production, you're probably okay - the subscription fee is more for up2dates and support for anything else.
) the license!
