diff --git a/tests/test_build87_penalty_strength_rebalance.py b/tests/test_build87_penalty_strength_rebalance.py
new file mode 100644
index 0000000..4e48df2
--- /dev/null
+++ b/tests/test_build87_penalty_strength_rebalance.py
@@ -0,0 +1,24 @@
+from pathlib import Path
+
+ROOT = Path(__file__).resolve().parents[1]
+APP_JS = (ROOT / "ui_builder/static/app.js").read_text(encoding="utf-8")
+
+
+def test_authoritative_strength_change_rebalances_penalty_targets():
+    start = APP_JS.index("function hockeyStoreGameControl")
+    end = APP_JS.index("async function hockeyLoadGameControl", start)
+    block = APP_JS[start:end]
+    assert "const strengthChanged" in block
+    assert "hockeyStrengthMappingSignature(previousControl) !== hockeyStrengthMappingSignature(payload)" in block
+    assert "rebalanceVmixPenaltyTargets({ force: true, hideUnused: true })" in block
+    assert "Penalty strength rebalance error" in block
+
+
+def test_penalty_plan_still_routes_two_vs_one_to_advantage_side():
+    start = APP_JS.index("function penaltyDisplayEntriesByTargetSide")
+    end = APP_JS.index("function hockeyPenaltySideMappingDetail", start)
+    block = APP_JS[start:end]
+    assert 'if (advantageSide === "home")' in block
+    assert 'return { home: take(away), away: [], routedToAdvantage: true, advantageSide: "home" };' in block
+    assert 'if (advantageSide === "away")' in block
+    assert 'return { home: [], away: take(home), routedToAdvantage: true, advantageSide: "away" };' in block
diff --git a/ui_builder/static/app.js b/ui_builder/static/app.js
index 9a750f8..38058d9 100644
--- a/ui_builder/static/app.js
+++ b/ui_builder/static/app.js
@@ -11132,8 +11132,20 @@ function renderHockeyPenaltyDashboard(node, component, runtime) {
       { render }
     );
     hockeyBackupPlayerSelectionValues(gameId, payload?.values || {});
-    if (!previousControl || hockeyStrengthMappingSignature(previousControl) !== hockeyStrengthMappingSignature(payload)) {
+    const strengthChanged = !previousControl
+      || hockeyStrengthMappingSignature(previousControl) !== hockeyStrengthMappingSignature(payload);
+    if (strengthChanged) {
       hockeyRefreshVmixMappingForStrength(gameId, previousControl, payload).catch(() => {});
+      // BUILD87: penalty routing depends on the recalculated numerical strength.
+      // The local penalty editor can rebalance a few milliseconds before the
+      // timer save response arrives, while state.data still contains the old
+      // 4x4/5x5 strength. Re-run the routing as soon as the authoritative
+      // control payload is stored so 2 penalties vs 1 immediately becomes
+      // 3x4/4x3 and the plate moves to the team with the advantage.
+      if (state.activeHockeyVmixTimerSteps.size) {
+        rebalanceVmixPenaltyTargets({ force: true, hideUnused: true })
+          .catch((error) => console.error("Penalty strength rebalance error", error));
+      }
     }
     if (previousControl && hockeyTeamStateFlagSignature(previousControl) !== hockeyTeamStateFlagSignature(payload) && hockeyTeamStateScoreboardIsLive()) {
       hockeySyncTeamStateOverlays({ force: true }).catch((error) => console.error("vMix team-state overlay sync error", error));