An apparatus for a user equipment, UE, the apparatus comprising: a memory interface to send or receive, to or from a memory device, a value selected from a first timing advance, TA, command to adjust a first uplink transmission timing for a first serving cell of the UE or a second TA command to adjust a second uplink transmission timing for a second serving cell of the UE; and a baseband processor to: decode a first subframe corresponding to a first downlink transmission from the first serving cell to obtain the first TA command; determine, based on a first transmission time interval, TTI, length corresponding to the first serving cell, a first TA adjustment delay to apply the first TA command at a first subframe boundary after the first subframe; decode a second subframe corresponding to a second downlink transmission from the second serving cell to obtain the second TA command; determine, based on a second TTI length corresponding to the second serving cell, a second TA adjustment delay to apply to the second TA command at a second subframe boundary after the second subframe, wherein the second TTI length is different than the first TTI length; select (608, 610), when the first TA adjustment delay and the second TA adjustment delay are equal, the value from either the first TA command or the second TA command; and adjust (608, 610), based on the value selected from either the first TA command or the second TA command, the first uplink transmission timing and the second uplink transmission timing. a memory interface to send or receive, to or from a memory device, a value selected from a first timing advance, TA, command to adjust a first uplink transmission timing for a first serving cell of the UE or a second TA command to adjust a second uplink transmission timing for a second serving cell of the UE; and a baseband processor to: decode a first subframe corresponding to a first downlink transmission from the first serving cell to obtain the first TA command; determine, based on a first transmission time interval, TTI, length corresponding to the first serving cell, a first TA adjustment delay to apply the first TA command at a first subframe boundary after the first subframe; decode a second subframe corresponding to a second downlink transmission from the second serving cell to obtain the second TA command; determine, based on a second TTI length corresponding to the second serving cell, a second TA adjustment delay to apply to the second TA command at a second subframe boundary after the second subframe, wherein the second TTI length is different than the first TTI length; select (608, 610), when the first TA adjustment delay and the second TA adjustment delay are equal, the value from either the first TA command or the second TA command; and adjust (608, 610), based on the value selected from either the first TA command or the second TA command, the first uplink transmission timing and the second uplink transmission timing. decode a first subframe corresponding to a first downlink transmission from the first serving cell to obtain the first TA command; determine, based on a first transmission time interval, TTI, length corresponding to the first serving cell, a first TA adjustment delay to apply the first TA command at a first subframe boundary after the first subframe; decode a second subframe corresponding to a second downlink transmission from the second serving cell to obtain the second TA command; determine, based on a second TTI length corresponding to the second serving cell, a second TA adjustment delay to apply to the second TA command at a second subframe boundary after the second subframe, wherein the second TTI length is different than the first TTI length; select (608, 610), when the first TA adjustment delay and the second TA adjustment delay are equal, the value from either the first TA command or the second TA command; and adjust (608, 610), based on the value selected from either the first TA command or the second TA command, the first uplink transmission timing and the second uplink transmission timing.