diff --git a/src/lib/sponsorship-subscription/reservation.test.ts b/src/lib/sponsorship-subscription/reservation.test.ts
index 38184ab..0fd897a 100644
--- a/src/lib/sponsorship-subscription/reservation.test.ts
+++ b/src/lib/sponsorship-subscription/reservation.test.ts
@@ -35,14 +35,21 @@ function productRow(product: FakeProduct) {
 
 function fakeDb(data: {
   quarterly?: { offer: { honeyJars: number } }[];
-  windows?: { offerId: string; startsOn: Date; endsOn: Date; plannedJars: number }[];
+  windows?: { offerId: string; startsOn: Date; endsOn: Date; plannedJars: number; offer?: { honeyJars: number } }[];
   deliveries?: { jars: number; dueAt: Date; subscription: { offerId: string } }[];
+  /** Laufende Abos je Ernte-Angebot (groupBy). */
+  ernteActive?: { offerId: string; count: number }[];
   products?: FakeProduct[];
   inventory?: { productId: string; quantity: number }[];
 }) {
   return {
-    sponsorshipSubscription: { findMany: vi.fn(async () => data.quarterly ?? []) },
-    harvestWindow: { findMany: vi.fn(async () => data.windows ?? []) },
+    sponsorshipSubscription: {
+      findMany: vi.fn(async () => data.quarterly ?? []),
+      groupBy: vi.fn(async () => (data.ernteActive ?? []).map((row) => ({ offerId: row.offerId, _count: { _all: row.count } }))),
+    },
+    harvestWindow: {
+      findMany: vi.fn(async () => (data.windows ?? []).map((window) => ({ offer: { honeyJars: 3 }, ...window }))),
+    },
     subscriptionDelivery: { findMany: vi.fn(async () => data.deliveries ?? []) },
     product: { findMany: vi.fn(async () => (data.products ?? []).map(productRow)) },
     inventory: {
@@ -82,6 +89,28 @@ describe("subscriptionReservedJars", () => {
     expect(await subscriptionReservedJars(NOW, db as unknown as Db)).toBe(2 + 2 + 3 + (10 - 4));
   });
 
+  test("Erntefenster: laufende Abos reservieren mindestens ihren Bedarf, auch ohne Planung", async () => {
+    const db = fakeDb({
+      windows: [
+        { offerId: "ernte", startsOn: new Date("2026-10-01T00:00:00.000Z"), endsOn: new Date("2026-10-31T00:00:00.000Z"), plannedJars: 0 },
+      ],
+      ernteActive: [{ offerId: "ernte", count: 4 }],
+    });
+
+    expect(await subscriptionReservedJars(NOW, db as unknown as Db)).toBe(4 * 3);
+  });
+
+  test("Erntefenster: nur das naechste Fenster je Angebot zaehlt", async () => {
+    const db = fakeDb({
+      windows: [
+        { offerId: "ernte", startsOn: new Date("2026-10-01T00:00:00.000Z"), endsOn: new Date("2026-10-31T00:00:00.000Z"), plannedJars: 6 },
+        { offerId: "ernte", startsOn: new Date("2027-06-01T00:00:00.000Z"), endsOn: new Date("2027-06-30T00:00:00.000Z"), plannedJars: 30 },
+      ],
+    });
+
+    expect(await subscriptionReservedJars(NOW, db as unknown as Db)).toBe(6);
+  });
+
   test("ein ueberliefertes Erntefenster reserviert nichts mehr (nie negativ)", async () => {
     const db = fakeDb({
       windows: [
diff --git a/src/lib/sponsorship-subscription/reservation.ts b/src/lib/sponsorship-subscription/reservation.ts
index 478ad7b..921e215 100644
--- a/src/lib/sponsorship-subscription/reservation.ts
+++ b/src/lib/sponsorship-subscription/reservation.ts
@@ -60,29 +60,53 @@ export async function subscriptionReservedJars(now: Date = new Date(), db: Db =
   const quarterlyJars = quarterly.reduce((sum, subscription) => sum + subscription.offer.honeyJars, 0);
 
   const today = startOfUtcDay(now);
-  const windows = await db.harvestWindow.findMany({
+  const allWindows = await db.harvestWindow.findMany({
     where: { endsOn: { gte: today }, offer: { cycle: "ERNTE" } },
-    select: { offerId: true, startsOn: true, endsOn: true, plannedJars: true },
+    select: { offerId: true, startsOn: true, endsOn: true, plannedJars: true, offer: { select: { honeyJars: true } } },
+    orderBy: { startsOn: "asc" },
   });
-  if (windows.length === 0) return quarterlyJars;
+  // Nur das jeweils NAECHSTE Fenster je Angebot zaehlt: jedes Abo bekommt
+  // hoechstens eine Lieferung je Fenster, und spaetere Fenster werden aus
+  // spaeterer Ernte bedient. Alle offenen Fenster zu reservieren, hielte heute
+  // Honig fuer eine Ernte fest, die es noch gar nicht gibt.
+  const nextByOffer = new Map<string, (typeof allWindows)[number]>();
+  for (const window of allWindows) if (!nextByOffer.has(window.offerId)) nextByOffer.set(window.offerId, window);
+  if (nextByOffer.size === 0) return quarterlyJars;
+
+  // Bedarf des Fensters: was der Inhaber geplant hat, mindestens aber, was
+  // die laufenden Abos dieses Angebots im Fenster beanspruchen koennen. So
+  // bleibt kein neues Abo ohne Honig, nur weil die Planung noch nicht
+  // nachgezogen wurde.
+  const ernteSubscriptions = await db.sponsorshipSubscription.groupBy({
+    by: ["offerId"],
+    where: {
+      status: { in: [...RESERVING_STATUSES] },
+      NOT: { status: "IM_VERZUG", payments: { some: { reversedAt: { not: null } } } },
+      offerId: { in: [...nextByOffer.keys()] },
+    },
+    _count: { _all: true },
+  });
+  const activeByOffer = new Map(ernteSubscriptions.map((group) => [group.offerId, group._count._all]));
 
   // Alle in den offenen Fenstern bereits angelegten Lieferungen in einer
   // Abfrage; die Zuordnung zum Fenster geschieht hier im Speicher.
-  const earliest = new Date(Math.min(...windows.map((window) => window.startsOn.getTime())));
+  const nextWindows = [...nextByOffer.values()];
+  const earliest = new Date(Math.min(...nextWindows.map((window) => window.startsOn.getTime())));
   const deliveries = await db.subscriptionDelivery.findMany({
     where: {
       status: "ANGELEGT",
-      subscription: { offerId: { in: [...new Set(windows.map((window) => window.offerId))] } },
+      subscription: { offerId: { in: [...nextByOffer.keys()] } },
       dueAt: { gte: earliest },
     },
     select: { jars: true, dueAt: true, subscription: { select: { offerId: true } } },
   });
-  const harvestJars = windows.reduce((sum, window) => {
+  const harvestJars = nextWindows.reduce((sum, window) => {
     const until = endOfUtcDay(window.endsOn);
     const delivered = deliveries
       .filter((d) => d.subscription.offerId === window.offerId && d.dueAt >= window.startsOn && d.dueAt <= until)
       .reduce((jars, d) => jars + d.jars, 0);
-    return sum + Math.max(0, window.plannedJars - delivered);
+    const needed = Math.max(window.plannedJars, (activeByOffer.get(window.offerId) ?? 0) * window.offer.honeyJars);
+    return sum + Math.max(0, needed - delivered);
   }, 0);
   return quarterlyJars + harvestJars;
 }