Quote - I've now heard back from e-on.  Apparently the intention of the message is that you aren't allowed to do something like sell your old V5I to somebody while continuing to use your V6I upgrade yourself, or have one person using your old V5I on one computer while you use the V6I upgrade on another one.  It was apparently not the intention for of the message to imply that you couldn't continue to use both apps on the one computer.  The wording didn't look that way, but apparently that's what's going on.

I updated a couple of days ago and also got this message. I was also worried about this message as V6I is still buggy. However, I could still use V5I after the update but felt uneasy doing so because of that message. I'm pleased to have clarification about what it meant because I too took it to mean I couldn't use V5I legally anymore.