EB1b I-140 premium processing (ask Xiaobaitu again)

My EB1b I-140 was filed to NSC by my attorney last Oct. Now I want to change it to premium processing. Need I have to ask my attorney to I-907, $1000 check, and copy of I-140 or I can do it by myself? I am asking as my attorney asks for extra money to do so. If it has to be done and through my attorney, then I will pay him the extra money.

Thanks a million and sorry can't type Chinese.