diff --git a/disk/src/binned.rs b/disk/src/binned.rs
index 8e8f015..6676d54 100644
--- a/disk/src/binned.rs
+++ b/disk/src/binned.rs
@@ -6,12 +6,13 @@ use crate::channelconfig::{extract_matching_config_entry, read_local_config};
 use crate::frame::makeframe::make_frame;
 use crate::raw::EventsQuery;
 use bytes::Bytes;
+use chrono::{TimeZone, Utc};
 use err::Error;
 use futures_core::Stream;
 use futures_util::StreamExt;
 use netpod::log::*;
 use netpod::{BinnedRange, NodeConfigCached, PerfOpts, PreBinnedPatchIterator, PreBinnedPatchRange};
-use serde::{Deserialize, Serialize};
+use serde::{Deserialize, Serialize, Serializer};
 use std::pin::Pin;
 use std::task::{Context, Poll};
 use std::time::Duration;
@@ -137,17 +138,45 @@ where
     }
 }
 
+struct Bool {}
+
+impl Bool {
+    pub fn is_false(x: &bool) -> bool {
+        *x == false
+    }
+}
+
+#[derive(Clone, Debug, Deserialize)]
+pub struct IsoDateTime(chrono::DateTime<Utc>);
+
+impl Serialize for IsoDateTime {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        serializer.serialize_str(&self.0.format("%Y-%m-%dT%H:%M:%S.%3fZ").to_string())
+    }
+}
+
 #[derive(Debug, Serialize, Deserialize)]
 pub struct BinnedJsonResult {
-    ts_bin_edges: Vec<u64>,
+    ts_bin_edges: Vec<IsoDateTime>,
     counts: Vec<u64>,
+    #[serde(skip_serializing_if = "Bool::is_false")]
+    partial_content: bool,
+    #[serde(skip_serializing_if = "Bool::is_false")]
+    finalised_range: bool,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    continue_at: Option<IsoDateTime>,
 }
 
 pub async fn binned_json(node_config: &NodeConfigCached, query: &BinnedQuery) -> Result<serde_json::Value, Error> {
-    let deadline = tokio::time::Instant::now() + Duration::from_millis(0);
+    let deadline = tokio::time::Instant::now() + Duration::from_millis(1000);
     let mut batch = MinMaxAvgScalarBinBatch::empty();
     let mut items = binned_stream(node_config, query).await?;
     let mut i1 = 0;
+    let mut partial_content = false;
+    let mut finalised_range = false;
     loop {
         let item = if i1 == 0 {
             items.next().await
@@ -155,7 +184,7 @@ pub async fn binned_json(node_config: &NodeConfigCached, query: &BinnedQuery) ->
             match tokio::time::timeout_at(deadline, items.next()).await {
                 Ok(k) => k,
                 Err(_) => {
-                    error!("TIMEOUT");
+                    partial_content = true;
                     None
                 }
             }
@@ -166,7 +195,7 @@ pub async fn binned_json(node_config: &NodeConfigCached, query: &BinnedQuery) ->
                 match item {
                     Ok(item) => match item {
                         Values(mut vals) => {
-                            info!("APPEND BATCH  {}", vals.ts1s.len());
+                            // TODO gather stats about the batch sizes.
                             batch.ts1s.append(&mut vals.ts1s);
                             batch.ts2s.append(&mut vals.ts2s);
                             batch.counts.append(&mut vals.counts);
@@ -177,23 +206,41 @@ pub async fn binned_json(node_config: &NodeConfigCached, query: &BinnedQuery) ->
                         }
                         Log(_) => {}
                         EventDataReadStats(_) => {}
-                        RangeComplete => {}
+                        RangeComplete => {
+                            finalised_range = true;
+                        }
                     },
                     Err(e) => {
                         // TODO  Need to use some flags to get good enough error message for remote user.
-                        Err(e)?
+                        Err(e)?;
                     }
                 };
             }
             None => break,
         }
     }
-    let mut ret = BinnedJsonResult {
-        ts_bin_edges: batch.ts1s,
-        counts: batch.counts,
-    };
+    let mut tsa: Vec<_> = batch
+        .ts1s
+        .iter()
+        .map(|&k| IsoDateTime(Utc.timestamp_nanos(k as i64)))
+        .collect();
     if let Some(&z) = batch.ts2s.last() {
-        ret.ts_bin_edges.push(z);
+        tsa.push(IsoDateTime(Utc.timestamp_nanos(z as i64)));
     }
+    let continue_at = if partial_content {
+        match tsa.last() {
+            Some(k) => Some(k.clone()),
+            None => Err(Error::with_msg("partial_content but no bin in result"))?,
+        }
+    } else {
+        None
+    };
+    let ret = BinnedJsonResult {
+        ts_bin_edges: tsa,
+        counts: batch.counts,
+        partial_content,
+        finalised_range,
+        continue_at,
+    };
     Ok(serde_json::to_value(ret)?)
 }