Sidelink downlink control information (SL DCI) associated with transmission of one or more sidelink signals may be communicated. A wireless user device may transmit, based on the SL DCI and to one or more second wireless user devices, the one or more sidelink signals via a first quantity of sidelink channel resources. The wireless user device may receive first sidelink HARQ feedback information responsive to the one or more sidelink signals. The wireless user device may determine, based on a sidelink HARQ feedback timing, a time interval to transmit the first sidelink HARQ feedback information. The wireless user device may determine, based on the first quantity, a sidelink HARQ codebook. The wireless user device may transmit, during the time interval, based on the sidelink HARQ codebook, and to the base station, an uplink signal indicating the first sidelink HARQ feedback information.