In aspects, a user equipment (UE) forms groups of overlapping uplink transmissions among component carriers (CCs), and moves in time all uplink transmissions within a group, except an earliest transmission, to align leading edges. The UE then determines, for each uplink transmission, if a joint timeline is satisfied, and allocates total transmission power depending on whether the timeline is satisfied for all uplink transmissions. In aspects, a base station transmits, to a UE, a transmit power configuration that identifies a reserved power for uplink transmissions of cell groups. The base station then transmits, to the UE, an uplink grant or configuration that identifies a transmission power for a cell group in excess of its reserved power, and receives, from the UE, uplink transmissions that exhibit an allocation of total transmission power according to the reserved power and the transmission power for the cell group in excess of the reserved power.