change period name in GL

accountant created calendar in GL, but named the periods wrong. Unfortunately, batches have been posted against these wrong periods. When tried to correct the period name on the GL Calendar form, it gave error message that Name can only be changed if it has not been used. Per oracle documents and support, it seems it cannot be done since many applications also use the same GL periods names. Has anyone had any luck in correcting the period name and please provide the script if any. Thanks.

James