Today around 12PM my office UTM (software version installed on old UTM120) alerted about new firmware version and offered the upgrade to GA. Does that mean that partner license is related to email address from which the trial or beta was downloaded ?
Yes, partners do still have access to not-for-resale licenses. The request can be sent to your local Channel Account Manager and they will help get the license processed for you.
There is no connection between the Partner NFR licenses and any Trial or Beta that you have already done.