A method of operation by a wireless device configured for operation in a wireless communication network , the method comprising: receiving sidelink configuration information for a second cell (22-2) of the wireless communication network via a cellular connection with a first cell (22-1), to be used during a cellular handover process to the second cell, the sidelink configuration information indicating sidelink resources and sidelink timing using a sidelink timing reference associated with the second cell (22-2); receiving handover signaling indicating a cellular handover of the wireless device from the first cell (22-1) of the wireless communication network to the second cell (22-2), and, in response: performing a cellular handover process with respect to the second cell (22-2), including performing a cellular synchronization process with respect to the second cell (22-2) using a downlink timing reference; and performing a sidelink synchronization process with respect to the second cell (22-2) using the sidelink timing reference, and resuming or initiating sidelink communications using the sidelink resources and the sidelink timing associated with the second cell (22-2) during the cellular handover process, once sidelink synchronized with respect to the second cell (22-2) via the sidelink synchronization process, wherein the sidelink timing reference is different than the downlink timing reference. receiving sidelink configuration information for a second cell (22-2) of the wireless communication network via a cellular connection with a first cell (22-1), to be used during a cellular handover process to the second cell, the sidelink configuration information indicating sidelink resources and sidelink timing using a sidelink timing reference associated with the second cell (22-2); receiving handover signaling indicating a cellular handover of the wireless device from the first cell (22-1) of the wireless communication network to the second cell (22-2), and, in response: performing a cellular handover process with respect to the second cell (22-2), including performing a cellular synchronization process with respect to the second cell (22-2) using a downlink timing reference; and performing a sidelink synchronization process with respect to the second cell (22-2) using the sidelink timing reference, and resuming or initiating sidelink communications using the sidelink resources and the sidelink timing associated with the second cell (22-2) during the cellular handover process, once sidelink synchronized with respect to the second cell (22-2) via the sidelink synchronization process, performing a cellular handover process with respect to the second cell (22-2), including performing a cellular synchronization process with respect to the second cell (22-2) using a downlink timing reference; and performing a sidelink synchronization process with respect to the second cell (22-2) using the sidelink timing reference, and resuming or initiating sidelink communications using the sidelink resources and the sidelink timing associated with the second cell (22-2) during the cellular handover process, once sidelink synchronized with respect to the second cell (22-2) via the sidelink synchronization process, wherein the sidelink timing reference is different than the downlink timing reference. <EOS>