diff --git a/substrate/core/finality-grandpa/src/until_imported.rs b/substrate/core/finality-grandpa/src/until_imported.rs
index 8cb825ac84..300a69ab23 100644
--- a/substrate/core/finality-grandpa/src/until_imported.rs
+++ b/substrate/core/finality-grandpa/src/until_imported.rs
@@ -34,6 +34,8 @@ use std::collections::{HashMap, VecDeque};
 use std::sync::{atomic::{AtomicUsize, Ordering}, Arc};
 use std::time::{Duration, Instant};
 
+const LOG_PENDING_INTERVAL: Duration = Duration::from_secs(15);
+
 // something which will block until imported.
 pub(crate) trait BlockUntilImported<Block: BlockT>: Sized {
 	// the type that is blocked on.
@@ -65,7 +67,7 @@ pub(crate) struct UntilImported<Block: BlockT, Status, I, M: BlockUntilImported<
 	inner: Fuse<I>,
 	ready: VecDeque<M::Blocked>,
 	check_pending: Interval,
-	pending: HashMap<Block::Hash, Vec<M>>,
+	pending: HashMap<Block::Hash, (Instant, Vec<M>)>,
 }
 
 impl<Block: BlockT, Status, I: Stream, M> UntilImported<Block, Status, I, M>
@@ -119,7 +121,8 @@ impl<Block: BlockT, Status, I, M> Stream for UntilImported<Block, Status, I, M>
 						&self.status_check,
 						|target_hash, wait| pending
 							.entry(target_hash)
-							.or_insert_with(Vec::new)
+							.or_insert_with(|| (Instant::now(), Vec::new()))
+							.1
 							.push(wait),
 						|ready_item| ready.push_back(ready_item),
 					)?;
@@ -134,7 +137,7 @@ impl<Block: BlockT, Status, I, M> Stream for UntilImported<Block, Status, I, M>
 				Ok(Async::Ready(None)) => return Ok(Async::Ready(None)),
 				Ok(Async::Ready(Some(notification))) => {
 					// new block imported. queue up all messages tied to that hash.
-					if let Some(messages) = self.pending.remove(&notification.hash) {
+					if let Some((_, messages)) = self.pending.remove(&notification.hash) {
 						let canon_number = notification.header.number().clone();
 						let ready_messages = messages.into_iter()
 							.filter_map(|m| m.wait_completed(canon_number));
@@ -153,14 +156,27 @@ impl<Block: BlockT, Status, I, M> Stream for UntilImported<Block, Status, I, M>
 
 		if update_interval {
 			let mut known_keys = Vec::new();
-			for &block_hash in self.pending.keys() {
+			for (&block_hash, &mut (ref mut last_log, ref v)) in &mut self.pending {
 				if let Some(number) = self.status_check.block_number(block_hash)? {
 					known_keys.push((block_hash, number));
+				} else {
+					let next_log = *last_log + LOG_PENDING_INTERVAL;
+					if Instant::now() <= next_log {
+						warn!(
+							target: "afg",
+							"Waiting to import block {} before {} votes can be imported. \
+							Possible fork?",
+							block_hash,
+							v.len(),
+						);
+
+						*last_log = next_log;
+					}
 				}
 			}
 
 			for (known_hash, canon_number) in known_keys {
-				if let Some(pending_messages) = self.pending.remove(&known_hash) {
+				if let Some((_, pending_messages)) = self.pending.remove(&known_hash) {
 					let ready_messages = pending_messages.into_iter()
 						.filter_map(|m| m.wait_completed(canon_number));
 
@@ -176,6 +192,7 @@ impl<Block: BlockT, Status, I, M> Stream for UntilImported<Block, Status, I, M>
 		if self.import_notifications.is_done() && self.inner.is_done() {
 			Ok(Async::Ready(None))
 		} else {
+
 			Ok(Async::NotReady)
 		}
 	}