Final answer:
The relieving unit should occupy positions that provide natural concealment and strategic advantages, such as raised and sunny spots next to slopes to remain out of enemy sight during a relief. Coordination with allies at key terrain points, such as high roads intersections, can also aid in maintaining concealment and surprise.
Step-by-step explanation:
To conceal the relief in place from the enemy during a sequential or staggered relief, the relieving unit should occupy positions that maximize concealment and surprise. Based on various military strategic principles, they can achieve this by taking up positions that are not easily visible to the enemy.
One effective tactic is to occupy raised and sunny spots that can serve as vantage points. As per the tactical advice provided, "When you come to a hill or a bank, occupy the sunny side, with the slope on your right rear." This uses the natural advantages of the terrain to benefit the soldiers in the relieving unit while also staying concealed.
The use of stratagems and choosing the right terrain—for instance, avoiding dangerously isolated positions—are also crucial. High roads intersection is an ideal position to join forces with allies, indicating the relieving unit should coordinate closely with adjacent friendly units to enhance the effectiveness of their positions.