When the passwords are lifted, it will become "as clear as mud". The simple, but wholly incomplete, answer is "Penalty Planes".
19. Penalty Planes - players that commit errors in basic rules and do not attempt to correct the error during play will have a penalty plane assigned to them to conduct a hair-raising mission behind enemy lines. If they survive they can teleport and replane in their regular ride. Examples of penalty plane errors include flying different a/c during a frame, teleporting fields when not allowed by special rules, gunning from ships or flak positions. If a player immediately addresses the error they will not be assigned a penalty plane but always inform the CM so the log entry will be ignored. It is up to each squad to make sure the penalty planes are flown.
Axis Penalty Planes - Bf110G2
Allied Penalty Plane - Hurricane IIC
I suspect that the use of the Bf 110G-2 in lieu of other "Rides and Sides" scheduled airplanes during the Series had some influence on the decision to allow the "downgrade" to the Hurri IIc. Only one "penalty plane" was listed for each "side".