diff --git a/core/crates/sync/src/ingest.rs b/core/crates/sync/src/ingest.rs
index c37ec4efc..c4bf2a09e 100644
--- a/core/crates/sync/src/ingest.rs
+++ b/core/crates/sync/src/ingest.rs
@@ -116,28 +116,30 @@ impl Actor {
 		}
 	}
 
+	// where the magic happens
 	async fn receive_crdt_operation(&mut self, op: CRDTOperation) {
+		// first, we update the HLC's timestamp with the incoming one.
+		// this involves a drift check + sets the last time of the clock
 		self.clock
 			.update_with_timestamp(&Timestamp::new(op.timestamp, op.instance.into()))
-			.ok();
+			.expect("timestamp has too much drift!");
 
-		let mut timestamp = {
-			let mut clocks = self.timestamps.write().await;
-			*clocks.entry(op.instance).or_insert_with(|| op.timestamp)
-		};
-
-		if timestamp < op.timestamp {
-			timestamp = op.timestamp;
-		}
+		// read the timestamp for the operation's instance, or insert one if it doesn't exist
+		let timestamp = self.timestamps.write().await.get(&op.instance).cloned();
 
+		// copy some fields bc rust ownership
 		let op_instance = op.instance;
+		let op_timestamp = op.timestamp;
 
-		let is_old = self.compare_message(&op).await;
-
-		if !is_old {
+		if !self.is_operation_old(&op).await {
+			// actually go and apply the operation in the db
 			self.apply_op(op).await.ok();
 
-			self.timestamps.write().await.insert(op_instance, timestamp);
+			// update the stored timestamp for this instance - will be derived from the crdt operations table on restart
+			self.timestamps.write().await.insert(
+				op_instance,
+				NTP64::max(timestamp.unwrap_or_default(), op_timestamp),
+			);
 		}
 	}
 
@@ -145,11 +147,13 @@ impl Actor {
 		self.db
 			._transaction()
 			.run(|db| async move {
+				// apply the operation to the actual record
 				ModelSyncData::from_op(op.clone())
 					.unwrap()
 					.exec(&db)
 					.await?;
 
+				// write the operation to the operations table
 				write_crdt_op_to_db(&op, &db).await?;
 
 				Ok(())
@@ -161,7 +165,8 @@ impl Actor {
 		Ok(())
 	}
 
-	async fn compare_message(&mut self, op: &CRDTOperation) -> bool {
+	// determines if an operation is old and shouldn't be applied
+	async fn is_operation_old(&mut self, op: &CRDTOperation) -> bool {
 		let db = &self.db;
 
 		let old_timestamp = {