Are you offering nvUltra as a purchasable app, or just a subscription? You've dawdled so long on the first release that it's almost vaporware at this point. Perhaps sell the first version, then once you've demonstrated that you have a modicum of credibility in upholding your commitments to your customers under a subscription model, you could try it on a limited basis?
Anyone on the beta knows that we're perfectly capable up upholding a regular release schedule. Just because we've had some hiccups reaching a public release is not an indicator that development isn't happening on a timely basis.