I have exactly the same thing and it is annoying. When I start my PC the first thing that pops up in the bottom right corner is a message that my license has expired. It stays there for something like 30 seconds or so and then vanishes. The exact message is: "The license key that you are using has expired".
I have a fast PC and a fast internet connection. It feels as though CCleaner is already checking license information before it is completely ready to do so.