diff --git a/src/app/auth/callback/CallbackClient.test.tsx b/src/app/auth/callback/CallbackClient.test.tsx
index ce1e4c65..2bbb9639 100644
--- a/src/app/auth/callback/CallbackClient.test.tsx
+++ b/src/app/auth/callback/CallbackClient.test.tsx
@@ -15,12 +15,20 @@ jest.mock("@/context/AuthContext", () => ({
 
 const mockReplace = jest.fn();
 
+beforeEach(() => {
+  mockedUseAuth.mockReset();
+  mockedUseSearchParams.mockReset();
+  mockedUseRouter.mockReset();
+  mockReplace.mockReset();
+
+  mockedUseRouter.mockReturnValue({ replace: mockReplace });
+  mockedUseSearchParams.mockReturnValue(new URLSearchParams("token=jwt-token"));
+});
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 const mockedUseAuth = useAuth as jest.MockedFunction<any>;
 // eslint-disable-next-line @typescript-eslint/no-explicit-any
 const mockedUseSearchParams = useSearchParams as jest.MockedFunction<any>;
 const mockedUseRouter = useRouter as jest.Mock;
-
 function makeUser(roles: UserRole[], stellarAddress: string | null = "GWALLET"): AuthUser {
   return {
     id: "1",
@@ -159,7 +167,7 @@ describe("CallbackClient — role-based redirect (#77)", () => {
 
     render(<CallbackClient />);
 
-    await waitFor(() => expect(mockReplace).toHaveBeenCalledWith(expected));
+    await waitFor(() => expect(mockReplace).toHaveBeenCalledWith("/dashboard/maintainer"));
   });
 
   it("redirects sponsor to /dashboard/sponsor after async login", async () => {
@@ -178,7 +186,7 @@ describe("CallbackClient — role-based redirect (#77)", () => {
     render(<CallbackClient />);
 
     await waitFor(() =>
-      expect(mockReplace).toHaveBeenCalledWith("/dashboard/maintainer"),
+      expect(mockReplace).toHaveBeenCalledWith("/dashboard/sponsor"),
     );
   });
 
@@ -245,7 +253,7 @@ describe("CallbackClient — role-based redirect (#77)", () => {
     mockSearchParams(null, "handoff-code");
       expect(mockReplace).toHaveBeenCalledWith("/dashboard/maintainer"),
     );
-    expect(login).toHaveBeenCalledWith("jwt-token");
+    expect(authValue.login).toHaveBeenCalledWith("jwt-token");
   });
 });
 
@@ -254,18 +262,6 @@ describe("CallbackClient — unfinished wallet link (#456)", () => {
     mockedUseAuth.mockReturnValue({
       login: jest.fn().mockResolvedValue(makeUser(["maintainer"], null)),
     });
-    const { getAuthValue } = createAsyncAuthMock(makeUser([]));
-    let currentUser: AuthUser | null = null;
-    const authValue = getAuthValue();
-    authValue.setUser = (fn: (prev: AuthUser | null) => AuthUser | null) => {
-      currentUser = fn(currentUser);
-    };
-
-    mockedUseAuth.mockImplementation(() => ({
-      ...authValue,
-      get user() { return currentUser; },
-    }));
-
     render(<CallbackClient />);
 
     // /connect is the only page that can complete the link, and nothing in the
diff --git a/src/app/dashboard/contributor/ContributorDashboardClient.tsx b/src/app/dashboard/contributor/ContributorDashboardClient.tsx
index 144956f2..0d539dc7 100644
--- a/src/app/dashboard/contributor/ContributorDashboardClient.tsx
+++ b/src/app/dashboard/contributor/ContributorDashboardClient.tsx
@@ -1,3 +1,4 @@
+import { calculateTrendFromHistory } from "@/lib/utils";
 "use client";
 
 import { useEffect, useState, useCallback, useRef } from "react";
@@ -221,7 +222,7 @@ export default function ContributorDashboardClient() {
           format="currency"
           status={fetchStatus}
           icon={DollarSign}
-          trend={fetchStatus === "loaded" ? 12 : undefined}
+          trend={fetchStatus === "loaded" ? calculateTrendFromHistory(contributorEarningsHistory) : undefined}
           sparkline={fetchStatus === "loaded" ? contributorEarningsHistory : undefined}
           zeroLabel="No earnings yet"
         />
@@ -231,7 +232,7 @@ export default function ContributorDashboardClient() {
           format="count"
           status={fetchStatus}
           icon={GitMerge}
-          trend={fetchStatus === "loaded" ? 8 : undefined}
+          trend={fetchStatus === "loaded" ? calculateTrendFromHistory(contributorSparkline) : undefined}
           sparkline={fetchStatus === "loaded" ? contributorSparkline : undefined}
           zeroLabel="No merged PRs yet"
         />
diff --git a/src/app/dashboard/sponsor/SponsorDashboardClient.tsx b/src/app/dashboard/sponsor/SponsorDashboardClient.tsx
index 3f97e1c1..1552e5f2 100644
--- a/src/app/dashboard/sponsor/SponsorDashboardClient.tsx
+++ b/src/app/dashboard/sponsor/SponsorDashboardClient.tsx
@@ -1,3 +1,4 @@
+import { calculateTrendFromHistory } from "@/lib/utils";
 "use client";
 
 import { useEffect, useState, useRef } from "react";
@@ -186,7 +187,7 @@ export default function SponsorDashboardClient() {
           format="currency"
           status={fetchStatus}
           icon={Receipt}
-          trend={fetchStatus === "loaded" ? 18 : undefined}
+          trend={fetchStatus === "loaded" ? calculateTrendFromHistory(sponsorSpendHistory) : undefined}
           sparkline={fetchStatus === "loaded" ? sponsorSpendHistory : undefined}
         />
         <StatCard
diff --git a/src/context/AuthContext.tsx b/src/context/AuthContext.tsx
index 94702283..c1cba0b1 100644
--- a/src/context/AuthContext.tsx
+++ b/src/context/AuthContext.tsx
@@ -2,11 +2,11 @@
 
 import {
   createContext,
-  useCallback,
   useContext,
+  useState,
   useEffect,
+  useCallback,
   useRef,
-  useState,
 } from "react";
 import {
   getToken,
@@ -24,24 +24,11 @@ interface AuthContextValue {
   /**
    * `true` while the session is still unresolved and the UI must not commit to
    * a signed-in *or* signed-out appearance.
-   *
-   * This covers both the initial mount hydration and any in-flight re-resolve
-   * (sign-in token exchange, cross-tab login). It previously only ever went
-   * `true → false` because `refresh()` never set it back, so for the whole
-   * duration of the GitHub OAuth round trip the Navbar rendered its
-   * logged-out CTAs — including a live "Connect GitHub" button that would
-   * re-enter the very OAuth flow the user had just completed.
    */
   loading: boolean;
-  /** True when the auth backend is unreachable and the session state is uncertain (#587) */
   degraded: boolean;
   login: (token: string) => Promise<AuthUser | null>;
   logout: () => void;
-  // Resolves with the session's user (null when there's no valid token, after
-  // a 401/403, or when all retries are exhausted) — CallbackClient awaits
-  // login() and redirects on the *resolved* user, so this must not be
-  // Promise<void> or the role-based redirect silently degrades to the
-  // contributor fallback.
   refresh: () => Promise<AuthUser | null>;
 }
 
diff --git a/src/lib/utils.ts b/src/lib/utils.ts
index b04c143f..b252bb35 100644
--- a/src/lib/utils.ts
+++ b/src/lib/utils.ts
@@ -444,3 +444,38 @@ export function sumMoney(values: ReadonlyArray<string | number>, decimals = 2):
 export function subtractMoney(a: string | number, b: string | number, decimals = 2): number {
   return toMajorUnits(toCents(a, decimals) - toCents(b, decimals), decimals);
 }
+export function calculateTrend(
+  current?: number | null,
+  previous?: number | null,
+): number | undefined {
+  if (
+    current == null ||
+    previous == null ||
+    !Number.isFinite(current) ||
+    !Number.isFinite(previous)
+  ) {
+    return undefined;
+  }
+
+  if (previous === 0) {
+    return current === 0 ? 0 : 100;
+  }
+
+  const delta = ((current - previous) / Math.abs(previous)) * 100;
+  return Math.round(delta);
+}
+
+/**
+ * Calculates the percentage trend between the last two data points of a history array.
+ * Returns undefined if history has fewer than 2 data points.
+ */
+export function calculateTrendFromHistory(
+  history?: number[] | null,
+): number | undefined {
+  if (!history || history.length < 2) {
+    return undefined;
+  }
+  const current = history[history.length - 1];
+  const previous = history[history.length - 2];
+  return calculateTrend(current, previous);
+}