diff --git a/main.go b/main.go
index 4274b58..6421f96 100644
--- a/main.go
+++ b/main.go
@@ -801,6 +801,13 @@ func handleListConstraints(db *sql.DB) http.HandlerFunc {
 			Level        string `json:"level"`
 		}
 		var overalls []overallEntry
+		type mismatchEntry struct {
+			NameA string `json:"name_a"`
+			NameB string `json:"name_b"`
+			KindA string `json:"kind_a"`
+			KindB string `json:"kind_b"`
+		}
+		var mismatches []mismatchEntry
 
 		if role == "admin" {
 			type pairKey struct{ a, b int64 }
@@ -865,6 +872,27 @@ func handleListConstraints(db *sql.DB) http.HandlerFunc {
 					constraints[i].Override = &desc
 				}
 			}
+			overallMap := map[pairKey]overallEntry{}
+			for _, o := range overalls {
+				overallMap[pairKey{o.StudentAID, o.StudentBID}] = o
+			}
+			for _, o := range overalls {
+				rev, ok := overallMap[pairKey{o.StudentBID, o.StudentAID}]
+				if !ok {
+					continue
+				}
+				if isPositive(o.Kind) && !isPositive(rev.Kind) {
+					mismatches = append(mismatches, mismatchEntry{
+						NameA: rev.StudentBName,
+						NameB: o.StudentBName,
+						KindA: o.Kind,
+						KindB: rev.Kind,
+					})
+				}
+			}
+		}
+		if mismatches == nil {
+			mismatches = []mismatchEntry{}
 		}
 		if overrides == nil {
 			overrides = []overrideEntry{}
@@ -874,7 +902,7 @@ func handleListConstraints(db *sql.DB) http.HandlerFunc {
 		}
 
 		w.Header().Set("Content-Type", "application/json")
-		json.NewEncoder(w).Encode(map[string]any{"constraints": constraints, "overrides": overrides, "overalls": overalls})
+		json.NewEncoder(w).Encode(map[string]any{"constraints": constraints, "overrides": overrides, "overalls": overalls, "mismatches": mismatches})
 	}
 }
 
diff --git a/static/trip.js b/static/trip.js
index 3b17cb7..4b97624 100644
--- a/static/trip.js
+++ b/static/trip.js
@@ -59,7 +59,6 @@ async function loadStudents() {
     const kindVariant = { must: 'success', prefer: 'brand', prefer_not: 'warning', must_not: 'danger' };
     const kindColor = { must: 'var(--wa-color-success-50)', prefer: 'var(--wa-color-brand-50)', prefer_not: 'var(--wa-color-warning-50)', must_not: 'var(--wa-color-danger-50)' };
     const kindOrder = { must: 0, prefer: 1, prefer_not: 2, must_not: 3 };
-    const isPositive = kind => kind === 'must' || kind === 'prefer';
     const capitalize = s => s.charAt(0).toUpperCase() + s.slice(1);
 
     const conflictMap = {};
@@ -82,21 +81,7 @@ async function loadStudents() {
     }
     lastOveralls = allOveralls;
 
-    const mismatchList = [];
-    for (const s of students) {
-        for (const [bId, effA] of Object.entries(allOveralls[s.id])) {
-            if (!allOveralls[bId] || !allOveralls[bId][s.id]) continue;
-            const effB = allOveralls[bId][s.id];
-            if (isPositive(effA.kind) && !isPositive(effB.kind)) {
-                mismatchList.push({
-                    nameA: s.name,
-                    nameB: students.find(x => x.id === parseInt(bId)).name,
-                    kindA: effA.kind,
-                    kindB: effB.kind,
-                });
-            }
-        }
-    }
+    const mismatchList = constraintData.mismatches;
 
     const studentName = {};
     for (const s of students) studentName[s.id] = s.name;
@@ -219,10 +204,10 @@ async function loadStudents() {
         for (const m of mismatchList) {
             const div = document.createElement('div');
             div.className = 'conflict-row';
-            div.appendChild(document.createTextNode(m.nameA + ' \u2192 ' + m.nameB + ': '));
-            div.appendChild(kindSpan(m.kindA));
-            div.appendChild(document.createTextNode(' but ' + m.nameB + ' \u2192 ' + m.nameA + ': '));
-            div.appendChild(kindSpan(m.kindB));
+            div.appendChild(document.createTextNode(m.name_a + ' \u2192 ' + m.name_b + ': '));
+            div.appendChild(kindSpan(m.kind_a));
+            div.appendChild(document.createTextNode(' but ' + m.name_b + ' \u2192 ' + m.name_a + ': '));
+            div.appendChild(kindSpan(m.kind_b));
             det.appendChild(div);
         }
         mismatchesEl.appendChild(det);