The timing for changing the correspondence address depends on the stage of the patent application process: Before filing an oath or declaration: You can change the address as provided in pre-AIA 37 CFR 1.33(a)(1). After filing an oath or declaration: The address can be changed as per pre-AIA 37 CFR 1.33(a)(2). The MPEP states: "The correspondence address may be changed as provided in pre-AIA 37 CFR 1.33(a)(1) prior to the filing of an oath or declaration. After an oath or declaration has been executed and filed by at least one inventor, the correspondence address may be changed as provided in pre-AIA 37 CFR 1.33(a)(2)." (MPEP 2542) To learn more: correspondence address patent application oath or declaration pre-AIA rules