During the last half of season 8, Catherine Bell was shown mostly behind a desk or holding something in front of her because she was pregnant. Her character pretended to be pregnant during the last couple of episodes of the 8th season, then threw away the padding during the Season 9 premiere - because Bell had given birth during the summer hiatus.
"JAG" stands for "Judge Advocate General". The office of JAG is a part of the Navy, which according to their official website "provides legal and policy advice to the Secretary of the Navy in all legal matters concerning military justice, administrative law, environmental law, ethics, claims, admiralty, operational and international law, litigation and legal assistance."
During Tracey Needham's time on the show, when wearing her ribbons, she was shown as wearing only the Meritorious Unit Commendation. She should also have been wearing the National Defense Medal which had been authorized for all service personnel serving during the period 2 Aug 1990 to 30 Nov 1995. Tracey Needham first appeared as Lt(jg) Meg Austin on 30 Sept 1995.
The location for Admiral Chegwidden's house is the Peter Strauss Ranch, operated by the National Park Service in the beautiful Santa Monica Mountains National Recreation Area in Southern California once owned by actor Peter Strauss.