diff --git a/cmd/vidforward/file.go b/cmd/vidforward/file.go
index 39ab39b1..f026da09 100644
--- a/cmd/vidforward/file.go
+++ b/cmd/vidforward/file.go
@@ -51,8 +51,7 @@ type BroadcastBasic struct {
 // ManagerBasic is a crude version of the BroadcastManager struct use to simplify
 // marshal/unmarshal overriding.
 type ManagerBasic struct {
-	Broadcasts       map[MAC]*Broadcast
-	SlateExitSignals []MAC
+	Broadcasts map[MAC]*Broadcast
 }
 
 // MarshalJSON calls the default marshalling behaviour for the BroadcastBasic
@@ -94,14 +93,7 @@ func (b *Broadcast) UnmarshalJSON(data []byte) error {
 // MarshalJSON calls the default marshaller for a ManagerBasic value using data
 // from a broadcastManager value.
 func (m *broadcastManager) MarshalJSON() ([]byte, error) {
-	var signals []MAC
-	for k := range m.slateExitSignals {
-		signals = append(signals, k)
-	}
-	return json.Marshal(ManagerBasic{
-		Broadcasts:       m.broadcasts,
-		SlateExitSignals: signals,
-	})
+	return json.Marshal(ManagerBasic{Broadcasts: m.broadcasts})
 }
 
 // UnmarshalJSON populates a ManagerBasic value from the provided data and then
@@ -123,20 +115,23 @@ func (m *broadcastManager) UnmarshalJSON(data []byte) error {
 	}
 	m.dogNotifier = notifier
 
-	for _, mac := range mb.SlateExitSignals {
-		sigCh := make(chan struct{})
-		m.slateExitSignals[mac] = sigCh
-		rv := m.getPipeline(mac)
-		if rv == nil {
-			panic("no pipeline for MAC")
-		}
-		if !inTest {
-			err := writeSlateAndCheckErrors(rv, sigCh, m.log)
-			if err != nil {
-				return fmt.Errorf("couldn't write slate for MAC %v: %w", mac, err)
+	for mac, b := range m.broadcasts {
+		if b.status == statusSlate {
+			sigCh := make(chan struct{})
+			m.slateExitSignals[mac] = sigCh
+			rv := m.getPipeline(mac)
+			if rv == nil {
+				panic("no pipeline for MAC")
+			}
+			if !inTest {
+				err := writeSlateAndCheckErrors(rv, sigCh, m.log)
+				if err != nil {
+					return fmt.Errorf("couldn't write slate for MAC %v: %w", mac, err)
+				}
 			}
 		}
 	}
+
 	return nil
 }