If you use SQL Server Management Studio to generate a script on an existing native log shipping setup, you need to be careful when using that generated script. Other than the fact that it lumps the SQL statements for different servers into the same script file, you may want to know that the copy and restore job schedules are not truthfully captured in the script. In fact, the schedules are not captured at all. The script simply chooses a default schedule regardless what your actual copy/restore schedules may be.
You may already know this, but I learned the hard way.