A relay node supporting mobile terminal (MT) functionality and distributed unit (DU) functionality may receive a timing advance (TA) value for uplink synchronization associated with a timing alignment timer from a parent node. In some cases, the timing alignment timer may expire prior to the relay node receiving a next TA value. Upon expiration of the timing alignment timer, the relay node may initiate a second timer (e.g., a transition timer) associated with the transitioning of a DU entity of the relay node to a DU transition state. The DU transition state is associated with certain DU behavior for serving child nodes while the transition timer is active. Configuration of the DU transition state may be identified by the relay node, or received from a parent node. In cases where the transition timer expires prior to receiving a next TA value, the DU may declare a loss of uplink synchronization.