I don't see that happening. They would have to offer support for the new product and most of my marketing is word of mouth nowadays. Should work out just fine ;)
Every open3ABox has an open websocket connection to my server. I do the monitoring over this connection and for updates and support I tell the box over the websocket connection to forward a port via ssh to my server. The port will be automatically closed by the open3ABox after three hours.
This means no constantly open port and an encrypted connection where only my server is allowed to do a remote function execution (get monitoring values, open port, etc.) on the box.
I do this because I'm in it for the long run. Sure, maybe it won't pay off, but my "first directive" is, to get people to use my open3A. If they've put all their data in it and miss some feature in the future it is more probable that they will just buy it from me instead of going through the hassle of moving to another solution. If they have a good support experience that just gives them a better feeling with my software.