///
/// use lightning_block_sync::*;
///
-/// use std::cell::RefCell;
/// use std::io::Cursor;
///
/// async fn init_sync<
/// ) {
/// // Read a serialized channel monitor paired with the block hash when it was persisted.
/// let serialized_monitor = "...";
-/// let (monitor_block_hash, mut monitor) = <(BlockHash, ChannelMonitor<S>)>::read(
+/// let (monitor_block_hash_option, mut monitor) = <(Option<BlockHash>, ChannelMonitor<S>)>::read(
/// &mut Cursor::new(&serialized_monitor), keys_manager).unwrap();
///
/// // Read the channel manager paired with the block hash when it was persisted.
/// let serialized_manager = "...";
-/// let (manager_block_hash, mut manager) = {
+/// let (manager_block_hash_option, mut manager) = {
/// let read_args = ChannelManagerReadArgs::new(
/// keys_manager,
/// fee_estimator,
/// config,
/// vec![&mut monitor],
/// );
-/// <(BlockHash, ChannelManager<S, &ChainMonitor<S, &C, &T, &F, &L, &P>, &T, &K, &F, &L>)>::read(
+/// <(Option<BlockHash>, ChannelManager<S, &ChainMonitor<S, &C, &T, &F, &L, &P>, &T, &K, &F, &L>)>::read(
/// &mut Cursor::new(&serialized_manager), read_args).unwrap()
/// };
///
/// // Synchronize any channel monitors and the channel manager to be on the best block.
/// let mut cache = UnboundedCache::new();
-/// let mut monitor_listener = (RefCell::new(monitor), &*tx_broadcaster, &*fee_estimator, &*logger);
-/// let listeners = vec![
-/// (monitor_block_hash, &mut monitor_listener as &mut dyn chain::Listen),
-/// (manager_block_hash, &mut manager as &mut dyn chain::Listen),
-/// ];
+/// let mut monitor_listener = (monitor, &*tx_broadcaster, &*fee_estimator, &*logger);
+/// let mut listeners = vec![];
+/// if let Some(monitor_block_hash) = monitor_block_hash_option {
+/// listeners.push((monitor_block_hash, &mut monitor_listener as &mut dyn chain::Listen))
+/// }
+/// if let Some(manager_block_hash) = manager_block_hash_option {
+/// listeners.push((manager_block_hash, &mut manager as &mut dyn chain::Listen))
+/// }
/// let chain_tip = init::synchronize_listeners(
/// block_source, Network::Bitcoin, &mut cache, listeners).await.unwrap();
///
/// // Allow the chain monitor to watch any channels.
-/// let monitor = monitor_listener.0.into_inner();
+/// let monitor = monitor_listener.0;
/// chain_monitor.watch_channel(monitor.get_funding_txo().0, monitor);
///
/// // Create an SPV client to notify the chain monitor and channel manager of block events.