An apparatus for use in a wireless communication network, comprising: a processing resource configured to: determine a time interval for periodic time division duplex, TDD, Uplink/Downlink, UL/DL, reconfiguration windows, wherein each UL/DL reconfiguration window comprises at least two radio frames; generate a UL/DL reconfiguration command to indicate a dynamic TDD UL/DL allocation change; and encode the UL/DL reconfiguration command in a physical downlink control channel, PDCCH, data; and a radio frequency, RF, interface coupled to the processing resource and configured to cause the encoded UL/DL reconfiguration command to be transmitted to a first of a plurality of wireless user equipment, UEs, in a first of the UL/DL reconfiguration windows, wherein the encoded UL/DL reconfiguration command is transmitted via a PDCCH to provide a fast TDD UL/DL reconfiguration; wherein the RF interface is further configured to communicate with the first UE on a first of a plurality of component carriers, CCs, and a second of the plurality of CCs, wherein the first CC is associated with a primary serving cell, PCell, wherein the second CC is associated with a secondary serving cell, SCell, wherein the UL/DL reconfiguration command comprises a first UL/DL configuration for the PCell and a second UL/DL configuration for the SCell, and wherein the PDCCH is associated with the PCell; and wherein to encode the UL/DL reconfiguration command, the processing resource is further configured to: encode the first UL/DL configuration in a first downlink control information, DCI, message according to a DCI format; and encode the second UL/DL configuration in a second DCI message according to the DCI format, and wherein to transmit the encoded UL/DL reconfiguration command, the RF interface is further configured to cause the first DCI message and the second DCI message to be transmitted in a common control portion of the PDCCH at different UL/DL reconfiguration schedules, the reconfiguration schedules comprising different periodicities, different subframe offsets with respect to a beginning of a radio frame, or combinations thereof. a processing resource configured to: determine a time interval for periodic time division duplex, TDD, Uplink/Downlink, UL/DL, reconfiguration windows, wherein each UL/DL reconfiguration window comprises at least two radio frames; generate a UL/DL reconfiguration command to indicate a dynamic TDD UL/DL allocation change; and encode the UL/DL reconfiguration command in a physical downlink control channel, PDCCH, data; and determine a time interval for periodic time division duplex, TDD, Uplink/Downlink, UL/DL, reconfiguration windows, wherein each UL/DL reconfiguration window comprises at least two radio frames; generate a UL/DL reconfiguration command to indicate a dynamic TDD UL/DL allocation change; and encode the UL/DL reconfiguration command in a physical downlink control channel, PDCCH, data; and a radio frequency, RF, interface coupled to the processing resource and configured to cause the encoded UL/DL reconfiguration command to be transmitted to a first of a plurality of wireless user equipment, UEs, in a first of the UL/DL reconfiguration windows, wherein the encoded UL/DL reconfiguration command is transmitted via a PDCCH to provide a fast TDD UL/DL reconfiguration; wherein the RF interface is further configured to communicate with the first UE on a first of a plurality of component carriers, CCs, and a second of the plurality of CCs, wherein the first CC is associated with a primary serving cell, PCell, wherein the second CC is associated with a secondary serving cell, SCell, wherein the UL/DL reconfiguration command comprises a first UL/DL configuration for the PCell and a second UL/DL configuration for the SCell, and wherein the PDCCH is associated with the PCell; and wherein to encode the UL/DL reconfiguration command, the processing resource is further configured to: encode the first UL/DL configuration in a first downlink control information, DCI, message according to a DCI format; and encode the second UL/DL configuration in a second DCI message according to the DCI format, and wherein to transmit the encoded UL/DL reconfiguration command, the RF interface is further configured to cause the first DCI message and the second DCI message to be transmitted in a common control portion of the PDCCH at different UL/DL reconfiguration schedules, the reconfiguration schedules comprising different periodicities, different subframe offsets with respect to a beginning of a radio frame, or combinations thereof. encode the first UL/DL configuration in a first downlink control information, DCI, message according to a DCI format; and encode the second UL/DL configuration in a second DCI message according to the DCI format, and wherein to transmit the encoded UL/DL reconfiguration command, the RF interface is further configured to cause the first DCI message and the second DCI message to be transmitted in a common control portion of the PDCCH at different UL/DL reconfiguration schedules, the reconfiguration schedules comprising different periodicities, different subframe offsets with respect to a beginning of a radio frame, or combinations thereof.