Local Rule 83-10 answers this question and provides the procedure for changes of address or firm affiliation. Note also that whenever an attorney leaves a firm, the firm is responsible for filing notices of substitution of counsel for any pending cases assigned to that attorney.
LR 83-10 Notification of Change of Address or Affiliation
(a) Current Address Information
Every attorney admitted to general or special practice, and every unrepresented party, has a continuing responsibility to notify the Clerk's office whenever their mailing address, telephone number, and/or business e-mail address changes. Commensurate with filing the notice to the Court, the attorney must update his/her CM/ECF User Account.
(b) Notice of Change of Mailing and/or Business E-Mail Address
Notice of a change of mailing and/or business e-mail address must be filed in pleading form and served on all parties to any pending action, or case on appeal.