Journey Log
Under latest rules you have to have a journey log for the aircraft. Trouble is the rules don't seem very specific about how far back it needs to go. Entries need to be signed by pilot. As I've always kept a "tech log" I'm using this with the addition of "usual captains signature" inside front cover. Not that I ever expect anybody ever to ask to see it..........
(It doesn't have to be carried in the aircraft, but be available if requested). Whereas your current journey, plog etc, does.