Im not sure exactly what would happen if I stopped the cream completely, but I can tell you that my lips are much healthier so I don't see them going back to the way they were quickly.
I saw a difference immediately. I can't really say how long it took to get to where they are now, it was pretty quick compared to other things I'd tried, and they just got better and better.
I apply it a few times daily. I just like how it makes my lips feel. If I let them go without it, it doesn't look bad. They just feel kinda dry. I haven't gone more than 24 hours without applying it though.
You'll have to try for yourself to see how often you need to put it on. You might not use it the same way I do. I'm interested to see another person's perspective on it.