diff --git a/src/ipv6rwc/ipv6rwc.go b/src/ipv6rwc/ipv6rwc.go
index f71c638e..fc2a688f 100644
--- a/src/ipv6rwc/ipv6rwc.go
+++ b/src/ipv6rwc/ipv6rwc.go
@@ -129,10 +129,10 @@ func (k *keyStore) sendToSubnet(subnet address.Subnet, bs []byte) {
 
 func (k *keyStore) update(key ed25519.PublicKey) *keyInfo {
 	k.mutex.Lock()
-	defer k.mutex.Unlock()
 	var kArray keyArray
 	copy(kArray[:], key)
 	var info *keyInfo
+	var packets [][]byte
 	if info = k.keyToInfo[kArray]; info == nil {
 		info = new(keyInfo)
 		info.key = kArray
@@ -142,15 +142,19 @@ func (k *keyStore) update(key ed25519.PublicKey) *keyInfo {
 		k.addrToInfo[info.address] = info
 		k.subnetToInfo[info.subnet] = info
 		if buf := k.addrBuffer[info.address]; buf != nil {
-			k.core.WriteTo(buf.packet, iwt.Addr(info.key[:]))
+			packets = append(packets, buf.packet)
 			delete(k.addrBuffer, info.address)
 		}
 		if buf := k.subnetBuffer[info.subnet]; buf != nil {
-			k.core.WriteTo(buf.packet, iwt.Addr(info.key[:]))
+			packets = append(packets, buf.packet)
 			delete(k.subnetBuffer, info.subnet)
 		}
 	}
 	k.resetTimeout(info)
+	k.mutex.Unlock()
+	for _, packet := range packets {
+		k.core.WriteTo(packet, iwt.Addr(info.key[:]))
+	}
 	return info
 }