61 Pa. Code § 703.6 – Service.

(a) A party shall serve the other party with each submission.
(b) Subsection (a) does not apply to the petition form and the first 20 pages of a submission filed with the petition which the Board will docket onto the Department’s appeal system.
(c) The Department will be deemed to be served electronically when the Board dockets the petition onto the Department’s appeal system.
(d) The preferred method of service is electronic. If electronic service is not available, service shall be by mail or in person using a method prescribed in § 702.4 (relating to filing generally).
(e) Subsection (a)—(d) supersedes 1 Pa. Code § § 33.31—-33.37 (relating to service of documents).

This section cited in 61 Pa. Code § 702.32 (relating to general rules).