To the extent a power of attorney expressly grants an agent authority over the content of electronic communications sent or received by the principal and unless directed otherwise by the principal or the court, a custodian shall disclose to the agent the content if the agent gives the custodian:
(a) A written request for disclosure in physical or electronic form;
(b) an original or copy of the power of attorney expressly granting the agent authority over the content of electronic communications of the principal;
(c) a certification by the agent, under penalty of perjury, that the power of attorney is in effect; and
(d) if requested by the custodian:
(1) A number, username, address or other unique subscriber or account identifier assigned by the custodian to identify the principal's account; or
(2) evidence linking the account to the principal.