diff --git a/static/multi_pu_dashboard.html b/static/multi_pu_dashboard.html
index 767015a..601b373 100644
--- a/static/multi_pu_dashboard.html
+++ b/static/multi_pu_dashboard.html
@@ -94,7 +94,7 @@ function initAllPlots() {
         y: [0],
         mode: 'lines',
         line: { dash: 'dash', color: 'red' },
-        name: `${plot.refKey} (PU3)`,
+        name: `${plot.refKey} (PU2)`,
         showlegend: true
       });
     }
@@ -144,7 +144,7 @@ async function updateAllPlots() {
 
     const SkidData = allData["PatientSkid"] || {};
     const DSData = allData["DS"] || {};
-    const pu3Data = allData["PU_3"] || {};  // <--- take ref values from PU_3
+    const pu2Data = allData["PU_2"] || {};  // <--- take ref values from PU_3
 
     plots.forEach(plot => {
       const xUpdates = [];
@@ -160,9 +160,9 @@ async function updateAllPlots() {
 
       Plotly.extendTraces(plot.id, { x: xUpdates, y: yUpdates }, puList.map((_, i) => i), maxPoints);
 
-      // Update PU3 reference line dynamically
+      // Update PU2 reference line dynamically
       if (plot.refKey) {
-        const refVal = pu3Data[plot.refKey];
+        const refVal = pu2Data[plot.refKey];
         const refIndex = puList.length; // because ref trace was pushed last
         Plotly.extendTraces(plot.id,
           { x: [[timestamp]], y: [[refVal ?? null]] },