A communications system, e.g. an Internet-of-Things (IoT) communications system, includes satellite gateways in addition to terrestrial gateways. High QoS end point devices utilize communications via satellite gateway to be able to communicate with a network server when communications with the network server via terrestrial gateways are unavailable or unreliable. Low QoS end point devices may communicate with the network server via terrestrial gateways but are restricted from using the satellite gateways. An additional receive window, corresponding to the satellite gateway, is used for communicating downlink signals from the satellite gateway to the high QoS end point device.