Rename Time Entry Paytype and create a new one

Hi, we are thinking of renaming an existing PAytype used for Time entry to make it as Training internal and create a new one as External. We dont have Payroll in the system just stand alone time entry. What are the implications on renaming this old paytype in regards to the previous entries and what do we need to consider with the new paytype. for AAIs, if they are the same as external, we can just use the same set as with the old paytype? Thanks