In one embodiment, a device in a network identifies a node in the network that is not synchronized to a network time synchronization mechanism. The device determines a scheduled reception time for a particular deterministic traffic flow at which the device is to receive the traffic flow from the node. The device sends, prior to the scheduled reception time, a request to the node for the particular deterministic traffic flow. The request identifies the particular deterministic traffic flow and causes the node to send the traffic flow to the device. The device receives the particular deterministic traffic flow from the node at the scheduled reception time.