Upgrading to Premium

I have a Lifetime subscription to manycam studio… right now my current version for my subscription is 5.7.2

If I upgraded to premium what would the cost be??

ANd Please what is Priority support?? is there a phone number??

I am considering an upgrade because I can not connect directly to twitch without OBS.

And my emails to support take a day or more to get a reply…

Any advice would be greatly appreciated.