diff --git a/CHANGELOG.md b/CHANGELOG.md
index 093593fcb67..35de9cada51 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -121,6 +121,7 @@ Docs: https://docs.openclaw.ai
 - Matrix/Directory room IDs: preserve original room-ID casing for direct `!roomId` group lookups (without `:server`) so allowlist checks do not fail on case-sensitive IDs. Landed from contributor PR #31201 by @williamos-dev. Thanks @williamos-dev.
 - Discord/Inbound media fallback: preserve attachment and sticker metadata when Discord CDN fetch/save fails by keeping URL-based media entries in context, with regression coverage for save failures and mixed success/failure ordering. Landed from contributor PR #28906 by @Sid-Qin. Thanks @Sid-Qin.
 - Auto-reply/Block reply timeout path: normalize `onBlockReply(...)` execution through `Promise.resolve(...)` before timeout wrapping so mixed sync/async callbacks keep deterministic timeout behavior across strict TypeScript build paths. (#19779) Thanks @dalefrieswthat and @vincentkoc.
+- Cron/One-shot reschedule re-arm: allow completed `at` jobs to run again when rescheduled to a later time than `lastRunAtMs`, while keeping completed non-rescheduled one-shot jobs inactive. (#28915) Thanks @Glucksberg.
 - Docs/Docker images: clarify the official GHCR image source and tag guidance (`main`, `latest`, `<version>`), and document that `OPENCLAW_IMAGE` skips local image builds but still uses the repo-local compose/setup flow. (#27214, #31180) Fixes #15655. Thanks @ipl31.
 - Docker/Image base annotations: add OCI labels for base image plus source/documentation/license metadata, include revision/version/created labels in Docker release builds, and document annotation keys/release context in install docs. Fixes #27945. Thanks @vincentkoc.
 - Agents/Model fallback: classify additional network transport errors (`ECONNREFUSED`, `ENETUNREACH`, `EHOSTUNREACH`, `ENETRESET`, `EAI_AGAIN`) as failover-worthy so fallback chains advance when primary providers are unreachable. Landed from contributor PR #19077 by @ayanesakura. Thanks @ayanesakura.
diff --git a/src/cron/service.issue-19676-at-reschedule.test.ts b/src/cron/service.issue-19676-at-reschedule.test.ts
new file mode 100644
index 00000000000..32139dd7ddf
--- /dev/null
+++ b/src/cron/service.issue-19676-at-reschedule.test.ts
@@ -0,0 +1,89 @@
+import { describe, expect, it } from "vitest";
+import { computeJobNextRunAtMs } from "./service/jobs.js";
+import type { CronJob } from "./types.js";
+
+const ORIGINAL_AT_MS = Date.parse("2026-02-22T10:00:00.000Z");
+const LAST_RUN_AT_MS = Date.parse("2026-02-22T10:00:05.000Z"); // ran shortly after scheduled time
+const RESCHEDULED_AT_MS = Date.parse("2026-02-22T12:00:00.000Z"); // rescheduled to 2 hours later
+
+function createAtJob(
+  overrides: { state?: CronJob["state"]; schedule?: CronJob["schedule"] } = {},
+): CronJob {
+  return {
+    id: "issue-19676",
+    name: "one-shot-reminder",
+    enabled: true,
+    createdAtMs: ORIGINAL_AT_MS - 60_000,
+    updatedAtMs: ORIGINAL_AT_MS - 60_000,
+    schedule: overrides.schedule ?? { kind: "at", at: new Date(ORIGINAL_AT_MS).toISOString() },
+    sessionTarget: "isolated",
+    wakeMode: "next-heartbeat",
+    payload: { kind: "agentTurn", message: "reminder" },
+    delivery: { mode: "none" },
+    state: { ...overrides.state },
+  };
+}
+
+describe("Cron issue #19676 at-job reschedule", () => {
+  it("returns undefined for a completed one-shot job that has not been rescheduled", () => {
+    const job = createAtJob({
+      state: { lastStatus: "ok", lastRunAtMs: LAST_RUN_AT_MS },
+    });
+    const nowMs = LAST_RUN_AT_MS + 1_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBeUndefined();
+  });
+
+  it("returns the new atMs when a completed one-shot job is rescheduled to a future time", () => {
+    const job = createAtJob({
+      schedule: { kind: "at", at: new Date(RESCHEDULED_AT_MS).toISOString() },
+      state: { lastStatus: "ok", lastRunAtMs: LAST_RUN_AT_MS },
+    });
+    const nowMs = LAST_RUN_AT_MS + 1_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBe(RESCHEDULED_AT_MS);
+  });
+
+  it("returns the new atMs when rescheduled via legacy numeric atMs field", () => {
+    const job = createAtJob({
+      state: { lastStatus: "ok", lastRunAtMs: LAST_RUN_AT_MS },
+    });
+    // Simulate legacy numeric atMs field on the schedule object.
+    const schedule = job.schedule as { kind: "at"; atMs?: number };
+    schedule.atMs = RESCHEDULED_AT_MS;
+    const nowMs = LAST_RUN_AT_MS + 1_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBe(RESCHEDULED_AT_MS);
+  });
+
+  it("returns undefined when rescheduled to a time before the last run", () => {
+    const beforeLastRun = LAST_RUN_AT_MS - 60_000;
+    const job = createAtJob({
+      schedule: { kind: "at", at: new Date(beforeLastRun).toISOString() },
+      state: { lastStatus: "ok", lastRunAtMs: LAST_RUN_AT_MS },
+    });
+    const nowMs = LAST_RUN_AT_MS + 1_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBeUndefined();
+  });
+
+  it("still returns atMs for a job that has never run", () => {
+    const job = createAtJob();
+    const nowMs = ORIGINAL_AT_MS - 60_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBe(ORIGINAL_AT_MS);
+  });
+
+  it("still returns atMs for a job whose last status is error", () => {
+    const job = createAtJob({
+      state: { lastStatus: "error", lastRunAtMs: LAST_RUN_AT_MS },
+    });
+    const nowMs = LAST_RUN_AT_MS + 1_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBe(ORIGINAL_AT_MS);
+  });
+
+  it("returns undefined for a disabled job even if rescheduled", () => {
+    const job = createAtJob({
+      schedule: { kind: "at", at: new Date(RESCHEDULED_AT_MS).toISOString() },
+      state: { lastStatus: "ok", lastRunAtMs: LAST_RUN_AT_MS },
+    });
+    job.enabled = false;
+    const nowMs = LAST_RUN_AT_MS + 1_000;
+    expect(computeJobNextRunAtMs(job, nowMs)).toBeUndefined();
+  });
+});
diff --git a/src/cron/service/jobs.ts b/src/cron/service/jobs.ts
index 7bb80ef37ac..740ddf83361 100644
--- a/src/cron/service/jobs.ts
+++ b/src/cron/service/jobs.ts
@@ -181,10 +181,6 @@ export function computeJobNextRunAtMs(job: CronJob, nowMs: number): number | und
     return isFiniteTimestamp(next) ? next : undefined;
   }
   if (job.schedule.kind === "at") {
-    // One-shot jobs stay due until they successfully finish.
-    if (job.state.lastStatus === "ok" && job.state.lastRunAtMs) {
-      return undefined;
-    }
     // Handle both canonical `at` (string) and legacy `atMs` (number) fields.
     // The store migration should convert atMs→at, but be defensive in case
     // the migration hasn't run yet or was bypassed.
@@ -197,6 +193,14 @@ export function computeJobNextRunAtMs(job: CronJob, nowMs: number): number | und
           : typeof schedule.at === "string"
             ? parseAbsoluteTimeMs(schedule.at)
             : null;
+    // One-shot jobs stay due until they successfully finish, but if the
+    // schedule was updated to a time after the last run, re-arm the job.
+    if (job.state.lastStatus === "ok" && job.state.lastRunAtMs) {
+      if (atMs !== null && Number.isFinite(atMs) && atMs > job.state.lastRunAtMs) {
+        return atMs;
+      }
+      return undefined;
+    }
     return atMs !== null && Number.isFinite(atMs) ? atMs : undefined;
   }
   const next = computeStaggeredCronNextRunAtMs(job, nowMs);