Two drones are flying in circular orbits around a tall structure at a constant altitude. Drone A has a circular orbit with radius (2r) and takes time (4T) to complete one full revolution around the structure. Drone B has a circular orbit with radius (2r + Δr) and takes time [4T + ΔT] to complete one full revolution, where Δr is much smaller than r and ΔT is much smaller than T. Determine the relationship between the changes in their revolution times and path radii.