Turn-based action is pre-computed with a "blue bar" before the action is displayed. This allows for improved performance of large battles on older computers, and for convenient "skipping ahead" in the early turns of a battle before enemy contact.
Suppressive fire: when you order direct fire at an enemy infantry unit, and that enemy unit later disappears from sight, the target order is not immediately canceled. Instead, your unit will continue to area-fire sporadically at the enemy's last known location for a short time if the LOS is sufficiently clear for area-style targeting (note that sometimes it won't be). Volume of fire is lighter versus open terrain, and shots will be taken at other targets of opportunity as usual. If the enemy reappears, it will again be targeted directly. If it does not reappear for about 45 seconds, the target order is canceled. A similar behavior applies to individual soldiers who have fired on enemy infantry without targeting orders from the player. They will continue to area-fire at their target's last known location for about 30 seconds.