Group transmission of data from a group of User Equipment devices to a network node of a cellular communication system where communication between devices is effected by device-to-device technology can provide significant improvements in uplink coverage and user bit rate. However, the benefits of group transmission means that not all devices of a group have sufficient network coverage to reliably receive a grant signal scheduling uplink resources from a network node. Methods, devices and a network node are proposed that enable the dynamic selection of either a direct grant mode, in which each device receives the uplink grant directly from the network, or a relayed grant mode, in which a device acting as group coordinator relays the grant to all members of the group, to ensure optimal performance for group transmissions. The selection is dependent on at least one determined condition relating to the group of devices and/or the group transmission. The group transmission is made by the group devices and received by the network node with a delay associated with the selected grant mode.