If a user goes to the normal user upgrade page, but they already purchased all available upgrades, they end up getting an error page and the server log gets 5 errors...
So the top 4 just follow on from the last one -- we don't kill execution on notices unless you're in debug mode.
The bottom one isn't directly from having every upgrade: it happens if you have upgrades A and B (A displayed before B), the user has A and B, and A disables access to B. The error comes from B already being removed from the list when A is processed.
Strange... if it's an issue of A disabling B, I would think we would see that error a LOT more. We have thousands of premium members... 6 different plans (all of which disable the other 5).