feat(api): rebook reviews into a 30-day interview sprint after the break

Review 4 closes out today (Nov 2); Reviews 7-20 move to Mon/Tue/Thu/Fri from
Fri Nov 6 to Tue Dec 1 (Thanksgiving unbooked), then two sweep days and a
gate: [] Saturday that makes Dec 5 day 30. The digest counts the sprint
(SPRINT_START, length derived from the plan's end) and counts down before it.
REVIEW_CAP 3 -> 5 so the ~110-review backlog drains inside the sprint.

apps/api/data/schedule.json

@@ -26,21 +26,24 @@
   "2026-10-02": { "review": { "issue": 226, "title": "Review 2 — Linear Structures", "problems": [290, 525, 189, 1004, 84] }, "sweep": true },
   "2026-10-03": { "gate": [] },
   "2026-10-05": { "review": { "issue": 227, "title": "Review 3 — Linear Structures", "problems": [643, 128, 162, 71, 4] } },
-  "2026-10-06": { "review": { "issue": 228, "title": "Review 4 — Linear Structures", "problems": [496, 80, 901, 76, 224] } },
   "2026-10-08": { "review": { "issue": 229, "title": "Review 5 — Nodal & Grid", "problems": [876, 19, 36] } },
   "2026-10-09": { "review": { "issue": 230, "title": "Review 6 — Nodal & Grid", "problems": [92, 82, 380] } },
-  "2026-10-12": { "review": { "issue": 231, "title": "Review 7 — Nodal & Grid", "problems": [143, 86, 289] } },
-  "2026-10-13": { "review": { "issue": 232, "title": "Review 8 — Nodal & Grid", "problems": [61, 138] } },
-  "2026-10-15": { "review": { "issue": 233, "title": "Review 9 — Hierarchical", "problems": [100, 112, 530, 1046, 103, 124] } },
-  "2026-10-16": { "review": { "issue": 234, "title": "Review 10 — Hierarchical", "problems": [572, 543, 703, 105, 295] } },
-  "2026-10-19": { "review": { "issue": 235, "title": "Review 11 — Hierarchical", "problems": [101, 637, 173, 621, 502] } },
-  "2026-10-20": { "review": { "issue": 236, "title": "Review 12 — Hierarchical", "problems": [108, 129, 373, 648, 212] } },
-  "2026-10-22": { "review": { "issue": 237, "title": "Review 13 — Relational", "problems": [1971, 695, 547, 433] } },
-  "2026-10-23": { "review": { "issue": 238, "title": "Review 14 — Relational", "problems": [130, 261, 909, 1462] } },
-  "2026-10-26": { "review": { "issue": 239, "title": "Review 15 — Relational", "problems": [286, 1254, 721, 399] } },
-  "2026-10-27": { "review": { "issue": 240, "title": "Review 16 — Relational", "problems": [1091, 802, 269] } },
-  "2026-10-29": { "review": { "issue": 241, "title": "Review 17 — Decision Space", "problems": [746, 228, 17, 77, 213, 63, 122] } },
-  "2026-10-30": { "review": { "issue": 242, "title": "Review 18 — Decision Space", "problems": [22, 90, 139, 120, 45, 253, 72] } },
-  "2026-11-02": { "review": { "issue": 243, "title": "Review 19 — Decision Space", "problems": [79, 131, 91, 494, 763, 986, 920] } },
-  "2026-11-03": { "review": { "issue": 244, "title": "Review 20 — Decision Space", "problems": [300, 647, 97, 221, 918, 452, 52] } }
+  "2026-11-02": { "review": { "issue": 228, "title": "Review 4 — Linear Structures", "problems": [496, 80, 901, 76, 224] } },
+  "2026-11-06": { "review": { "issue": 231, "title": "Review 7 — Nodal & Grid", "problems": [143, 86, 289] } },
+  "2026-11-09": { "review": { "issue": 232, "title": "Review 8 — Nodal & Grid", "problems": [61, 138] } },
+  "2026-11-10": { "review": { "issue": 233, "title": "Review 9 — Hierarchical", "problems": [100, 112, 530, 1046, 103, 124] } },
+  "2026-11-12": { "review": { "issue": 234, "title": "Review 10 — Hierarchical", "problems": [572, 543, 703, 105, 295] } },
+  "2026-11-13": { "review": { "issue": 235, "title": "Review 11 — Hierarchical", "problems": [101, 637, 173, 621, 502] } },
+  "2026-11-16": { "review": { "issue": 236, "title": "Review 12 — Hierarchical", "problems": [108, 129, 373, 648, 212] } },
+  "2026-11-17": { "review": { "issue": 237, "title": "Review 13 — Relational", "problems": [1971, 695, 547, 433] } },
+  "2026-11-19": { "review": { "issue": 238, "title": "Review 14 — Relational", "problems": [130, 261, 909, 1462] } },
+  "2026-11-20": { "review": { "issue": 239, "title": "Review 15 — Relational", "problems": [286, 1254, 721, 399] } },
+  "2026-11-23": { "review": { "issue": 240, "title": "Review 16 — Relational", "problems": [1091, 802, 269] } },
+  "2026-11-24": { "review": { "issue": 241, "title": "Review 17 — Decision Space", "problems": [746, 228, 17, 77, 213, 63, 122] } },
+  "2026-11-27": { "review": { "issue": 242, "title": "Review 18 — Decision Space", "problems": [22, 90, 139, 120, 45, 253, 72] } },
+  "2026-11-30": { "review": { "issue": 243, "title": "Review 19 — Decision Space", "problems": [79, 131, 91, 494, 763, 986, 920] } },
+  "2026-12-01": { "review": { "issue": 244, "title": "Review 20 — Decision Space", "problems": [300, 647, 97, 221, 918, 452, 52] } },
+  "2026-12-03": { "sweep": true },
+  "2026-12-04": { "sweep": true },
+  "2026-12-05": { "gate": [] }
 }

apps/api/src/digest.ts

@@ -10,12 +10,13 @@
  * either, so the rule holds by construction. The plan's own sections — a
  * learning day's topics (core, then the optional "if time" list), a set
  * day's problems, and a review day's `Review <N>` issue — are the only
- * labeled, linked ones. At most REVIEW_CAP (3)
+ * labeled, linked ones. At most REVIEW_CAP (5)
  * reviews per day; drills fill toward DAILY_CAP (6) only when the due queue
  * is light, and never on a sweep day, which assigns every open miss and
  * nothing new. Overflow is levelled, not stacked: sendDigest gives every
  * review past the cap a concrete future date, ≤ REVIEW_CAP per day, oldest
- * first. Sunday is a two-line rest note.
+ * first. Sunday is a two-line rest note. Day N/M counts the interview sprint
+ * (SPRINT_START → the plan's last day); before it, the email counts down.
  *
  * Idempotency: email_log keys sends by ET date — a same-day re-send is a
  * no-op unless forced; the body itself is deterministic (drill picks are
@@ -23,15 +24,15 @@
  * and a re-run finds nothing left over the cap.
  */
 import {
-  CAMPAIGN_DAYS,
   MISS_WHERE,
   type ProblemRow,
   RESERVED,
   REVIEW_CAP,
   SCHEDULE,
+  SPRINT_DAYS,
+  SPRINT_START,
   type ScheduledDay,
   addDays,
-  campaignDay,
   campaignWeek,
   dueReviews,
   isoWeek,
@@ -39,6 +40,8 @@ import {
   lookupProblems,
   pickDrills,
   prettyDate,
+  sprintDay,
+  sprintWeek,
   streak,
   weekdayOf,
 } from "./srs.ts";
@@ -107,9 +110,13 @@ export async function collectDigest(env: Env, date: string): Promise<DigestData>
   const drills =
     rest || plan.sweep ? [] : await pickDrills(db, date, DAILY_CAP - Math.min(due.length, DAILY_CAP));
 
+  const sprint = sprintDay(date);
   const data: DigestData = {
     day: prettyDate(date),
-    progress: `Day ${campaignDay(date)} of ${CAMPAIGN_DAYS} · Week ${campaignWeek(date)}`,
+    progress:
+      sprint >= 1
+        ? `Day ${sprint} of ${SPRINT_DAYS} · Week ${sprintWeek(date)}`
+        : `The ${SPRINT_DAYS}-day interview sprint starts ${prettyDate(SPRINT_START)}`,
     streak: await streak(db, date),
     rest,
     topics: [],
@@ -206,8 +213,13 @@ export async function collectDigest(env: Env, date: string): Promise<DigestData>
 export async function buildDigest(env: Env, date: string): Promise<Digest> {
   const data = await collectDigest(env, date);
   const { html, text } = await renderDigest(data);
+  const sprint = sprintDay(date);
+  const until = 1 - sprint;
   return {
-    subject: `(Day ${campaignDay(date)}/${CAMPAIGN_DAYS}) LeetCode Daily Digest`,
+    subject:
+      sprint >= 1
+        ? `(Day ${sprint}/${SPRINT_DAYS}) LeetCode Daily Digest`
+        : `(Sprint in ${until} ${until === 1 ? "day" : "days"}) LeetCode Daily Digest`,
     html,
     text,
   };

apps/api/src/email.tsx

@@ -108,7 +108,7 @@ export interface TopicSection {
 export interface DigestData {
   /** "Tuesday, August 25" */
   day: string;
-  /** "Day 9 of 79 · Week 2" — the length is CAMPAIGN_DAYS, derived from the plan. */
+  /** "Day 9 of 30 · Week 2" of the sprint (SPRINT_DAYS, derived from the plan), or its countdown before day 1. */
   progress: string;
   streak: number;
   rest: boolean;

apps/api/src/srs.test.ts

@@ -15,6 +15,12 @@ import {
   addDays,
   campaignDay,
   campaignWeek,
+  CAMPAIGN_DAYS,
+  CAMPAIGN_END,
+  SPRINT_DAYS,
+  SPRINT_START,
+  sprintDay,
+  sprintWeek,
   etDate,
   etHour,
   isRestDay,
@@ -28,8 +34,8 @@ import {
   workingDay,
 } from "./srs.ts";
 
-/** Every ET date of the campaign, plus the deferred-Hard tail. */
-const CALENDAR = Array.from({ length: 70 }, (_, i) => addDays("2026-08-17", i));
+/** Every ET date of the campaign (sprint included), plus two weeks of ladder tail. */
+const CALENDAR = Array.from({ length: CAMPAIGN_DAYS + 14 }, (_, i) => addDays("2026-08-17", i));
 
 describe("DST-proof cron guard", () => {
   test("digest fires only at ET hour 8 — EDT (UTC-4)", () => {
@@ -67,6 +73,15 @@ describe("date math (noon-UTC anchored)", () => {
     expect(campaignWeek("2026-08-30")).toBe(2);
     expect(campaignWeek("2026-08-31")).toBe(3);
   });
+  test("sprint math: day 1 is SPRINT_START, the last is the plan's end, weeks run Mon–Sun", () => {
+    expect(sprintDay(SPRINT_START)).toBe(1);
+    expect(sprintDay(addDays(SPRINT_START, -1))).toBe(0); // countdown, never "Day 0 of N"
+    expect(sprintDay(CAMPAIGN_END)).toBe(SPRINT_DAYS);
+    expect(sprintWeek("2026-11-06")).toBe(1); // Friday start
+    expect(sprintWeek("2026-11-08")).toBe(1); // its Sunday closes week 1
+    expect(sprintWeek("2026-11-09")).toBe(2);
+    expect(sprintWeek(CAMPAIGN_END)).toBe(5);
+  });
   test("iso week is stable across a week", () => {
     expect(isoWeek("2026-08-24")).toBe(isoWeek("2026-08-29"));
     expect(isoWeek("2026-08-30")).toBe(isoWeek("2026-08-24")); // Sun ends the ISO week

apps/api/src/srs.ts

@@ -166,6 +166,30 @@ export const SCHEDULE: Record<string, ScheduledDay> = scheduleJson;
 export const CAMPAIGN_END = Object.keys(SCHEDULE).sort().at(-1)!;
 export const CAMPAIGN_DAYS = daysBetween(CAMPAIGN_START, CAMPAIGN_END) + 1;
 
+/**
+ * Day 1 of the interview sprint: the plan restarted here after two weeks off,
+ * with every open Review issue rebooked between this Friday and CAMPAIGN_END.
+ * Only the start is declared; the length is derived like CAMPAIGN_DAYS, so
+ * booking a later day lengthens both. The digest counts days and weeks from
+ * here; the heatmaps and /api/stats keep the whole campaign.
+ */
+export const SPRINT_START = "2026-11-06";
+export const SPRINT_DAYS = daysBetween(SPRINT_START, CAMPAIGN_END) + 1;
+
+/** 1-based sprint day; zero or negative before SPRINT_START. */
+export function sprintDay(date: string): number {
+  return daysBetween(SPRINT_START, date) + 1;
+}
+
+/**
+ * 1-based sprint week, Mon–Sun like the campaign's, so the Friday start makes
+ * week 1 three days long and every later week a whole one.
+ */
+export function sprintWeek(date: string): number {
+  const monday = addDays(SPRINT_START, -((weekdayOf(SPRINT_START) + 6) % 7));
+  return Math.floor(daysBetween(monday, date) / 7) + 1;
+}
+
 /** Date the schedule teaches a topic on, if it teaches it at all. */
 export function topicDate(topic: number): string | undefined {
   for (const [date, day] of Object.entries(SCHEDULE)) {
@@ -413,8 +437,12 @@ export async function dueToday(db: D1Database, date: string): Promise<{ date: st
   };
 }
 
-/** Reviews surfaced per day; the digest levels everything past this forward. */
-export const REVIEW_CAP = 3;
+/**
+ * Reviews surfaced per day; the digest levels everything past this forward.
+ * 5, not 3, since the two-week break: at 3 a day the ~110-review backlog would
+ * outlast the sprint by a fortnight.
+ */
+export const REVIEW_CAP = 5;
 
 /**
  * Load-level an overloaded review queue: everything due beyond today's