Paths of semi-major axis versus eccentricity, and semi-major axis versus inclination for a representative set of three different PDS 70 systems. Panel (a): Isolated resonant PDS 70 system. Both planets remain planar and oscillate around their initial semi-major axis and eccentricity. No other changes occur. Panel (b): Perturbed resonant PDS 70 system. The planets lose their MMR due to a perturbation, and no stable orbit is found before a planet is lost. Panel (c): Perturbed resonant PDS 70 system. The planets remain in approximately the same orbits after a perturbation, though tilted and oscillating at a greater magnitude.