A method in a wireless device for determining a synchronization method to be used by the wireless device in a cellular communications network, the method in the wireless device comprising: receiving a maximum repetition value, Rmax value, from a network node, the Rmax value representing a maximum number of repetitions of signals transmitted by the network node in the cellular communications network; receiving a wake-up signal delta value, WUSdelta value, from the network node; the method in the wireless device being characterized by: determining the synchronization method to be used by the wireless device based on the Rmax value and the WUSdelta value by: - determining a WUSmax value based on the Rmax value and the WUSdelta value, the WUSmax value representing the maximum duration of a wake-up signal, WUS; and - determining the synchronization method to be used by the wireless device based on a comparison of the WUSmax value to a threshold, wherein when the WUSmax is greater than a threshold, the WUS is used for synchronization; and attempting to synchronize to the cellular communications network using the determined synchronization method, wherein, when the WUS is used for synchronization, attempting to synchronize to the cellular communications network comprises detecting the WUS, as transmitted from the network node. receiving a maximum repetition value, Rmax value, from a network node, the Rmax value representing a maximum number of repetitions of signals transmitted by the network node in the cellular communications network; receiving a wake-up signal delta value, WUSdelta value, from the network node; the method in the wireless device being characterized by: determining the synchronization method to be used by the wireless device based on the Rmax value and the WUSdelta value by: - determining a WUSmax value based on the Rmax value and the WUSdelta value, the WUSmax value representing the maximum duration of a wake-up signal, WUS; and - determining the synchronization method to be used by the wireless device based on a comparison of the WUSmax value to a threshold, wherein when the WUSmax is greater than a threshold, the WUS is used for synchronization; and attempting to synchronize to the cellular communications network using the determined synchronization method, wherein, when the WUS is used for synchronization, attempting to synchronize to the cellular communications network comprises detecting the WUS, as transmitted from the network node. determining the synchronization method to be used by the wireless device based on the Rmax value and the WUSdelta value by: - determining a WUSmax value based on the Rmax value and the WUSdelta value, the WUSmax value representing the maximum duration of a wake-up signal, WUS; and - determining the synchronization method to be used by the wireless device based on a comparison of the WUSmax value to a threshold, wherein when the WUSmax is greater than a threshold, the WUS is used for synchronization; and - determining a WUSmax value based on the Rmax value and the WUSdelta value, the WUSmax value representing the maximum duration of a wake-up signal, WUS; and - determining the synchronization method to be used by the wireless device based on a comparison of the WUSmax value to a threshold, wherein when the WUSmax is greater than a threshold, the WUS is used for synchronization; and attempting to synchronize to the cellular communications network using the determined synchronization method, wherein, when the WUS is used for synchronization, attempting to synchronize to the cellular communications network comprises detecting the WUS, as transmitted from the network node.