I saw this note on a linkedin post this morning and I immediately checked my calendar to see if it was April 1st today. Guess what, it isn’t….This bug will make SharePoint expire as though it was a trial installation 180 days after SP2 is deployed. Please check the original post on the msdn blogs here
To work around this issue you will need to re-enter their Product ID numbers (PID) on the Convert License Type page in Central Administration. Please see this KB article for detailed steps.