What is the elevation difference tolerance?

For stand count flight / analytics, you can fly the drone using terrain awareness mode which control drone to fly drone keeping the same relative altitude from the ground. Processing is compatible with terrain awareness flight. Fast stitching operation is not compatible with ground altitude difference within the field. But flying at 400ft, you could still have the reasonable quality of stitched images with approximately 30ft difference. If the stitched quality has affected much, then you might consider splitting the field and flight plan into multiple items.