diff --git a/src/runtime2/component/component.rs b/src/runtime2/component/component.rs
index 782399c46374828d05bb0b6074b2511e7de8a519..53c362b7058caf4c05f741de40eb19604767d410 100644
--- a/src/runtime2/component/component.rs
+++ b/src/runtime2/component/component.rs
@@ -577,7 +577,7 @@ pub(crate) fn default_handle_control_message(
 
                 if exec_state.mode.is_in_sync_block() {
                     let closed_during_sync_round = content.closed_in_sync_round && port_was_used;
-                    let closed_before_sync_round = !content.closed_in_sync_round && !port_has_had_message;
+                    let closed_before_sync_round = !content.closed_in_sync_round && !port_has_had_message && port_was_used;
 
                     if closed_during_sync_round || closed_before_sync_round {
                         return Err((
@@ -690,6 +690,13 @@ pub(crate) fn default_handle_start_exit(
     sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, consensus: &mut Consensus
 ) -> CompScheduling {
     debug_assert_eq!(exec_state.mode, CompMode::StartExit);
+    for port_index in 0..comp_ctx.num_ports() {
+        let port_info = comp_ctx.get_port_by_index_mut(port_index);
+        if port_info.state.is_blocked() {
+            return CompScheduling::Sleep;
+        }
+    }
+
     sched_ctx.info(&format!("Component starting exit (reason: {:?})", exec_state.exit_reason));
     exec_state.mode = CompMode::BusyExit;
     let exit_inside_sync = exec_state.exit_reason.is_in_sync();
@@ -704,7 +711,8 @@ pub(crate) fn default_handle_start_exit(
     // Iterating over ports by index to work around borrowing rules
     for port_index in 0..comp_ctx.num_ports() {
         let port = comp_ctx.get_port_by_index_mut(port_index);
-        if port.state.is_closed() || port.close_at_sync_end {
+        println!("DEBUG: Considering port:\n{:?}", port);
+        if port.state.is_closed() || port.state.is_set(PortStateFlag::Transmitted) || port.close_at_sync_end {
             // Already closed, or in the process of being closed
             continue;
         }
@@ -904,7 +912,7 @@ fn prepare_send_message_with_ports(
 /// all stored in the component's execution state by the
 /// `prepare_send_message_with_ports` function. Port must be ready to send!
 fn perform_send_message_with_ports(
-    exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx, comp_ctx: &CompCtx, consensus: &mut Consensus,
+    exec_state: &mut CompExecState, sched_ctx: &SchedulerCtx, comp_ctx: &mut CompCtx, consensus: &mut Consensus,
     inbox_main: &mut InboxMain, inbox_backup: &mut InboxBackup
 ) {
     debug_assert_eq!(exec_state.mode, CompMode::BlockedPutPortsReady);
@@ -941,7 +949,9 @@ fn perform_send_message_with_ports(
             peer_port: transmit_port_info.peer_port_id,
             kind: transmit_port_info.kind,
             state: transmit_port_state
-        })
+        });
+
+        comp_ctx.change_port_peer(sched_ctx, transmit_port_handle, None);
     }
 
     // And finally, send the message to the peer