A method for wireless communication at a user equipment, UE, comprising: receiving (1305; 1405), from a base station, an uplink grant for an uplink transmission from the UE to the base station; selecting (1310; 1410), based at least in part on the uplink grant, a packet transmission mode from a default transmission mode or a packet-group transmission mode for the uplink transmission, wherein the packet-group transmission mode specifies that a set of packets that are associated as a packet-group are included in a transmission payload of the uplink transmission, and the packet-group transmission mode is based at least in part on a packet transmission mode indicator included in the uplink grant, further comprising: identifying that the packet transmission mode indicator specifies the packet-group transmission mode, wherein a plurality of packets are organized in one or more packet-groups; determining (1315; 1420) one or more packets of the plurality of packets for inclusion in the transmission payload for the uplink transmission in accordance with the uplink grant and based at least in part on the selected packet transmission mode, the determining further comprising: identifying a resource capacity for the transmission payload; and determining the one or more packets such that the transmission payload comprises packets associated with a reduced quantity of packet-groups relative to a quantity of packet groups that the resource capacity supports and based at least in part on the transmission payload satisfying a capacity condition; and transmitting (1320; 1425), to the base station, the uplink transmission in accordance with the packet transmission mode and the uplink grant. receiving (1305; 1405), from a base station, an uplink grant for an uplink transmission from the UE to the base station; selecting (1310; 1410), based at least in part on the uplink grant, a packet transmission mode from a default transmission mode or a packet-group transmission mode for the uplink transmission, wherein the packet-group transmission mode specifies that a set of packets that are associated as a packet-group are included in a transmission payload of the uplink transmission, and the packet-group transmission mode is based at least in part on a packet transmission mode indicator included in the uplink grant, further comprising: identifying that the packet transmission mode indicator specifies the packet-group transmission mode, wherein a plurality of packets are organized in one or more packet-groups; determining (1315; 1420) one or more packets of the plurality of packets for inclusion in the transmission payload for the uplink transmission in accordance with the uplink grant and based at least in part on the selected packet transmission mode, the determining further comprising: identifying a resource capacity for the transmission payload; and determining the one or more packets such that the transmission payload comprises packets associated with a reduced quantity of packet-groups relative to a quantity of packet groups that the resource capacity supports and based at least in part on the transmission payload satisfying a capacity condition; and identifying a resource capacity for the transmission payload; and determining the one or more packets such that the transmission payload comprises packets associated with a reduced quantity of packet-groups relative to a quantity of packet groups that the resource capacity supports and based at least in part on the transmission payload satisfying a capacity condition; and transmitting (1320; 1425), to the base station, the uplink transmission in accordance with the packet transmission mode and the uplink grant.