diff --git a/tests/AcDream.Plugins.MossTank.Tests/NavigationTests.cs b/tests/AcDream.Plugins.MossTank.Tests/NavigationTests.cs
index fdac3af75..1c3ebd572 100644
--- a/tests/AcDream.Plugins.MossTank.Tests/NavigationTests.cs
+++ b/tests/AcDream.Plugins.MossTank.Tests/NavigationTests.cs
@@ -458,6 +458,82 @@ public sealed class NavigationTests
         Assert.Equal(-3, target.DoorLockpickExcessThreshold);
     }
 
+    /// <summary>
+    /// Reproduces MossTankRouteProfileStore's pre-cutover by-character JSON
+    /// hash key (its own <c>LegacyProfileKey</c> is private; the format is
+    /// the migration contract itself, reproduced verbatim here).
+    /// </summary>
+    private static string LegacyRouteByCharacterKey(string characterName)
+    {
+        string identity = "char:" + characterName.Trim().ToUpperInvariant();
+        string hash = Convert.ToHexString(
+            System.Security.Cryptography.SHA256.HashData(
+                System.Text.Encoding.UTF8.GetBytes(identity)));
+        return $"profiles/route/{hash}.json";
+    }
+
+    [Fact]
+    public void RouteStoreMigratesLegacyJsonProfileToAfAndDeletesTheJsonKey()
+    {
+        var storage = new MemoryStorage();
+        string legacyKey = LegacyRouteByCharacterKey("Barris");
+        storage.Text[legacyKey] = """
+            {
+              "Mode": 1,
+              "Waypoints": [
+                { "Type": 0, "EastWest": 5.0, "NorthSouth": 6.0 }
+              ]
+            }
+            """;
+
+        var store = new MossTankRouteProfileStore(new FakeHost(new FakeAutomation(), storage));
+        Assert.True(store.BindCharacter("Barris"));
+        var target = new NavigationSettings();
+        Assert.True(store.LoadCurrent(target, MetafSerializer.NoOpSpells.Instance));
+
+        Assert.False(storage.Text.ContainsKey(legacyKey));
+        Assert.Equal(RouteMode.Linear, target.Mode);
+        RouteWaypoint waypoint = Assert.Single(target.Waypoints);
+        // metaf's "pnt" node format is bare x/y/z (three doubles) — no cell
+        // id at all, for any waypoint type — so only the coordinates
+        // round-trip.
+        Assert.Equal(5.0d, waypoint.Position.EastWest, precision: 3);
+        Assert.Equal(6.0d, waypoint.Position.NorthSouth, precision: 3);
+
+        // Idempotent second run: nothing left to migrate.
+        var reopened = new MossTankRouteProfileStore(new FakeHost(new FakeAutomation(), storage));
+        Assert.True(reopened.BindCharacter("Barris"));
+        var reloaded = new NavigationSettings();
+        Assert.True(reopened.LoadCurrent(reloaded, MetafSerializer.NoOpSpells.Instance));
+        Assert.Single(reloaded.Waypoints);
+    }
+
+    [Fact]
+    public void RouteStoreLeavesLegacyJsonUntouchedWhenAfCounterpartExists()
+    {
+        var storage = new MemoryStorage();
+        string legacyKey = LegacyRouteByCharacterKey("Barris");
+        storage.Text[legacyKey] = """{ "Mode": 1, "Waypoints": [] }""";
+        string realKey = "nav_" + VtankProfileDirectory.AutoCharacterFileName(
+            "Barris", string.Empty, "af");
+        var real = new NavigationSettings { Mode = RouteMode.Circular };
+        real.Waypoints.Add(new RouteWaypoint
+        {
+            Type = RouteWaypointType.Point,
+            Position = new PluginNavigationPosition(0x00010001u, 1d, 2d, 0d, 0f, true),
+        });
+        storage.Text[realKey] = MetafSerializer.SaveNav(real);
+
+        var store = new MossTankRouteProfileStore(new FakeHost(new FakeAutomation(), storage));
+        Assert.True(store.BindCharacter("Barris"));
+        var target = new NavigationSettings();
+        Assert.True(store.LoadCurrent(target, MetafSerializer.NoOpSpells.Instance));
+
+        Assert.True(storage.Text.ContainsKey(legacyKey));
+        Assert.Equal(RouteMode.Circular, target.Mode);
+        Assert.Single(target.Waypoints);
+    }
+
     [Fact]
     public void FollowModeRouteRoundTripsTheFollowTargetThroughAf()
     {
@@ -619,6 +695,7 @@ public sealed class NavigationTests
     private sealed class MemoryStorage : IPluginStorage
     {
         private readonly Dictionary<string, string> _text = new(StringComparer.Ordinal);
+        public Dictionary<string, string> Text => _text;
         public bool IsAvailable => true;
         public string? ReadText(string key) =>
             _text.TryGetValue(key, out string? value) ? value : null;