A) Page 22, under "Routed Units and Heroes":
- "Routed units and heroes may not move or draw cards during battle. All units are stood up (un-routed) during each Spring (as part of the Spring Season card's secondary ability)."
Should read: Routed units and heroes may not move or draw cards during battle. All figures are stood up (un-routed) during each Spring (as part of the Spring Season card's secondary ability).
The rules explicitly numerous times describe that heroes are NOT units, and page 11 explains that the secondary ability of the Spring Season "instructs players to remove all activation tolkens from the game board and stand all routed figures (including neutral units and heroes)."
B) On this topic, I assume that it was intentional that on page 21 of the Battle section it states: "Heroes and routed units are not placed to the right of the player's faction sheet and, instead, remain in the contested area. These figures may not participate in battle, and these routed units are destroyed if forced to retreat."
This implies that heroes (even if routed) are not destroyed when an enemy takes their territory, since they are not UNITS but rather FIGURES.