There is provided a method performed by a wireless device for reconfiguring semi-persistent scheduling. The wireless device is configured with a first semi-persistent scheduling configuration for uplink or downlink transmissions. The method comprises: while semi-persistent scheduling is active according to the first semi-persistent scheduling configuration such that the wireless device is configured with periodic transmission or reception opportunities, receiving a semi-persistent scheduling reconfiguration message from a network node, the semi-persistent scheduling reconfiguration message comprising an instruction to reconfigure the wireless device to a second semi-persistent scheduling configuration for uplink or downlink transmissions; and determining one or more transmission or reception opportunities associated with the second semi-persistent scheduling configuration based on a semi-persistent scheduling activation time according to the second semi-persistent scheduling configuration.