A terminal device for use in a wireless telecommunications system, the terminal device comprising: a transceiver (500, 510) configured to perform wireless communication with a base station using a communications resource allocated to the terminal device by the base station; and a controller configured to: control the transceiver to receive a grant signal from the base station, the grant signal specifying a communications resource for use by the terminal device; control the transceiver to send a wireless message to the base station using the communications resource specified by the grant signal; determine, in dependence upon the grant signal, a subset, being some but not all, of a set of control data elements providing wireless signalling from the base station to the terminal device; and detect, from a control data element in the subset, acknowledgement information sent by the base station in respect of the wireless message, and characterized by that the controller is configured to detect the acknowledgement information from a signalling transmission comprising multiple instances of such information relating to respective wireless messages, and in which the multiple instances have a logical ordering, the controller being configured to select an instance from the multiple instances according to a mapping between the instances and a radio frequency used for sending the wireless message, and to detect the acknowledgement information from the selected instance. a transceiver (500, 510) configured to perform wireless communication with a base station using a communications resource allocated to the terminal device by the base station; and a controller configured to: control the transceiver to receive a grant signal from the base station, the grant signal specifying a communications resource for use by the terminal device; control the transceiver to send a wireless message to the base station using the communications resource specified by the grant signal; determine, in dependence upon the grant signal, a subset, being some but not all, of a set of control data elements providing wireless signalling from the base station to the terminal device; and detect, from a control data element in the subset, acknowledgement information sent by the base station in respect of the wireless message, and characterized by that the controller is configured to detect the acknowledgement information from a signalling transmission comprising multiple instances of such information relating to respective wireless messages, and in which the multiple instances have a logical ordering, the controller being configured to select an instance from the multiple instances according to a mapping between the instances and a radio frequency used for sending the wireless message, and to detect the acknowledgement information from the selected instance. control the transceiver to receive a grant signal from the base station, the grant signal specifying a communications resource for use by the terminal device; control the transceiver to send a wireless message to the base station using the communications resource specified by the grant signal; determine, in dependence upon the grant signal, a subset, being some but not all, of a set of control data elements providing wireless signalling from the base station to the terminal device; and detect, from a control data element in the subset, acknowledgement information sent by the base station in respect of the wireless message, and characterized by that the controller is configured to detect the acknowledgement information from a signalling transmission comprising multiple instances of such information relating to respective wireless messages, and in which the multiple instances have a logical ordering, the controller being configured to select an instance from the multiple instances according to a mapping between the instances and a radio frequency used for sending the wireless message, and to detect the acknowledgement information from the selected instance.