Update the demo date in order: first notary, then party nodes ordered by name.

samples/irs-demo/src/main/kotlin/net/corda/irs/flows/UpdateBusinessDayFlow.kt

@@ -51,11 +51,22 @@ object UpdateBusinessDayFlow {
         @Suspendable
         override fun call(): Unit {
             progressTracker.currentStep = NOTIFYING
-            for (recipient in serviceHub.networkMapCache.partyNodes.sortedBy { it.legalIdentity.name }) {
+            for (recipient in getRecipients()) {
                 doNextRecipient(recipient)
             }
         }
 
+        /**
+         * Returns recipients ordered by legal name, with notary nodes taking priority over party nodes.
+         * Ordering is required so that we avoid situations where on clock update a party starts a scheduled flow, but
+         * the notary or counterparty still use the old clock, so the timestamp on the transaction does not validate.
+         */
+        private fun getRecipients(): Iterable<NodeInfo> {
+            val notaryNodes = serviceHub.networkMapCache.notaryNodes
+            val partyNodes = (serviceHub.networkMapCache.partyNodes - notaryNodes).sortedBy { it.legalIdentity.name }
+            return notaryNodes + partyNodes
+        }
+
         @Suspendable
         private fun doNextRecipient(recipient: NodeInfo) {
             if (recipient.address is MockNetworkMapCache.MockAddress) {