I have the same issue, I've tried to contact support and got the same answer.
I told them at least they could offer a redeem code to restore the purchase if I bought the previous version, but no answer since.
It would be great if I won't have to buy the app again and again when there is a major upgrade, this is ridiculus.
I love using this application though, but I will have to look alternatives if this cannot be solved...
Update: Contacted support again, and they have provided a redeem code.