GITM Lines of Supply and Communication

To stay in communications and supply, units in GITM must have clear lines of supply and communication to a corps HQ. The corps HQ must have a clear line of communication to an army HQ, and to draw supplies from a city, must have a clear line of supply to the city. A line of contact exists between two units, or two cities, or a unit and a city, if there is a path between them such that:
  1. The path does not enter a square containing any enemy unit;
  2. The path does not enter a square adjacent to an enemy light cavalry or medium cavalry unit, unless there is a friendly combat (non-Q) unit in the square;
  3. The path does not pass diagonally between two squares both containing enemy units;
  4. The path does not enter impassible terrain;
  5. Each unit is able to move strategically off its current tactical map in the direction of the path, or in the case of cities, a unit located in the city tactical square could do so.
For example, if the situation is:

A1 A2 A3 A4 A5
AU1CQ       AU1AQ

then AU1AQ and AU1CQ are in contact along the path A2-S2, A3-S1, A4-S1, as long as AU1CQ can move strategically out of A1-S2 to the east, and AU1AQ can move strategically out of A5-S2 to the northwest. The line of contact cannot run through A3-S2 or A4-S2 because of FR1MC at A4-S3, but it may run through A2-S2, A3-S1, and A4-S1, because FR1IN at A2-S1 cannot block contact in adjacent squares.