diff --git a/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.test.tsx b/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.test.tsx
index 7240686a..dc72b72a 100644
--- a/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.test.tsx
+++ b/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.test.tsx
@@ -9,13 +9,17 @@ vi.mock("@/i18n/provider.js", () => ({
 
 describe("DaysOfWeekStrip", () => {
   it("renders 7 day boxes", () => {
-    render(<DaysOfWeekStrip flightBitString="1111111" />);
+    render(<DaysOfWeekStrip flightBitString="1234567" />);
     const boxes = screen.getAllByTestId(/^day-of-week-\d$/);
     expect(boxes).toHaveLength(7);
   });
 
-  it("marks first 3 active, last 4 inactive for '1110000'", () => {
-    render(<DaysOfWeekStrip flightBitString="1110000" />);
+  // Real API shape: `daysOfWeek.flight` is a STRING OF DIGITS where each
+  // character is the ISO weekday number of an active day (1=Mon..7=Sun).
+  // E.g. "156" means Mon + Fri + Sat are operating; "1234567" = every day.
+
+  it("marks Mon/Tue/Wed active, Thu-Sun inactive for '123'", () => {
+    render(<DaysOfWeekStrip flightBitString="123" />);
     expect(screen.getByTestId("day-of-week-0").className).not.toMatch(/--inactive/);
     expect(screen.getByTestId("day-of-week-1").className).not.toMatch(/--inactive/);
     expect(screen.getByTestId("day-of-week-2").className).not.toMatch(/--inactive/);
@@ -23,57 +27,52 @@ describe("DaysOfWeekStrip", () => {
     expect(screen.getByTestId("day-of-week-6").className).toMatch(/--inactive/);
   });
 
-  it("marks all active for '1111111'", () => {
-    render(<DaysOfWeekStrip flightBitString="1111111" />);
+  it("marks all active for '1234567'", () => {
+    render(<DaysOfWeekStrip flightBitString="1234567" />);
     for (let i = 0; i < 7; i++) {
       expect(screen.getByTestId(`day-of-week-${i}`).className).not.toMatch(/--inactive/);
     }
   });
 
-  it("marks all inactive for '0000000'", () => {
-    render(<DaysOfWeekStrip flightBitString="0000000" />);
+  it("marks all inactive for ''", () => {
+    render(<DaysOfWeekStrip flightBitString="" />);
     for (let i = 0; i < 7; i++) {
       expect(screen.getByTestId(`day-of-week-${i}`).className).toMatch(/--inactive/);
     }
   });
 
   it("renders DAYS.1 through DAYS.7 labels in order", () => {
-    render(<DaysOfWeekStrip flightBitString="1111111" />);
+    render(<DaysOfWeekStrip flightBitString="1234567" />);
     expect(screen.getByTestId("day-of-week-0").textContent).toContain("DAYS.1");
     expect(screen.getByTestId("day-of-week-6").textContent).toContain("DAYS.7");
   });
 
-  // TZ §4.1.16.8: position 0 = Monday (first ISO weekday), position 6 = Sunday
-  // Verify the Mon/Wed/Fri pattern used by typical schedule flights ("Пн Ср Пт" = "1010100")
-  it("Mon/Wed/Fri pattern: positions 0,2,4 active; 1,3,5,6 inactive", () => {
-    render(<DaysOfWeekStrip flightBitString="1010100" />);
-    // Active: Mon(0), Wed(2), Fri(4)
+  // Real-world: SU 6188 returns "156" → Mon, Fri, Sat operating.
+  it("Mon/Fri/Sat pattern '156': positions 0,4,5 active; 1,2,3,6 inactive", () => {
+    render(<DaysOfWeekStrip flightBitString="156" />);
     expect(screen.getByTestId("day-of-week-0").className).not.toMatch(/--inactive/);
-    expect(screen.getByTestId("day-of-week-2").className).not.toMatch(/--inactive/);
     expect(screen.getByTestId("day-of-week-4").className).not.toMatch(/--inactive/);
-    // Inactive: Tue(1), Thu(3), Sat(5), Sun(6)
+    expect(screen.getByTestId("day-of-week-5").className).not.toMatch(/--inactive/);
     expect(screen.getByTestId("day-of-week-1").className).toMatch(/--inactive/);
+    expect(screen.getByTestId("day-of-week-2").className).toMatch(/--inactive/);
     expect(screen.getByTestId("day-of-week-3").className).toMatch(/--inactive/);
-    expect(screen.getByTestId("day-of-week-5").className).toMatch(/--inactive/);
     expect(screen.getByTestId("day-of-week-6").className).toMatch(/--inactive/);
   });
 
-  // TZ §4.1.16.8: Sat/Sun only ("0000011")
-  it("weekend-only pattern: positions 5,6 active; 0-4 inactive", () => {
-    render(<DaysOfWeekStrip flightBitString="0000011" />);
-    for (let i = 0; i < 5; i++) {
-      expect(screen.getByTestId(`day-of-week-${i}`).className).toMatch(/--inactive/);
-    }
-    expect(screen.getByTestId("day-of-week-5").className).not.toMatch(/--inactive/);
-    expect(screen.getByTestId("day-of-week-6").className).not.toMatch(/--inactive/);
-  });
-
-  // TZ §4.1.16.8: single-day operation (Tuesday only = "0100000")
-  it("Tuesday-only pattern: position 1 active; all others inactive", () => {
-    render(<DaysOfWeekStrip flightBitString="0100000" />);
+  it("Tue-only '2': position 1 active; all others inactive", () => {
+    render(<DaysOfWeekStrip flightBitString="2" />);
     expect(screen.getByTestId("day-of-week-1").className).not.toMatch(/--inactive/);
     for (const i of [0, 2, 3, 4, 5, 6]) {
       expect(screen.getByTestId(`day-of-week-${i}`).className).toMatch(/--inactive/);
     }
   });
+
+  it("ignores non-digit characters and out-of-range digits", () => {
+    render(<DaysOfWeekStrip flightBitString="1x9 7" />);
+    expect(screen.getByTestId("day-of-week-0").className).not.toMatch(/--inactive/);
+    expect(screen.getByTestId("day-of-week-6").className).not.toMatch(/--inactive/);
+    for (const i of [1, 2, 3, 4, 5]) {
+      expect(screen.getByTestId(`day-of-week-${i}`).className).toMatch(/--inactive/);
+    }
+  });
 });
diff --git a/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.tsx b/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.tsx
index 78f109ea..5707fb95 100644
--- a/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.tsx
+++ b/src/features/online-board/components/FlightSchedule/DaysOfWeekStrip.tsx
@@ -2,6 +2,14 @@ import type { FC } from "react";
 import { useTranslation } from "@/i18n/provider.js";
 
 export interface DaysOfWeekStripProps {
+  /**
+   * Operating-days indicator from the API. The `daysOfWeek.flight` field
+   * is a STRING OF DIGITS (1=Mon..7=Sun), one digit per active day —
+   * NOT a 7-char bitmask. Examples: `"156"` = Mon/Fri/Sat;
+   * `"1234567"` = every day; `""` = none. Anything else (alternative
+   * shape, missing field) falls through to "all inactive" so the badge
+   * row still renders without crashing.
+   */
   flightBitString: string;
 }
 
@@ -9,11 +17,19 @@ const DAY_INDEXES = [0, 1, 2, 3, 4, 5, 6] as const;
 
 export const DaysOfWeekStrip: FC<DaysOfWeekStripProps> = ({ flightBitString }) => {
   const { t } = useTranslation();
+  // Build a Set<dayNumber> from the API string. Each character is a
+  // 1-based ISO weekday digit ("1" → Mon, …, "7" → Sun).
+  const activeDays = new Set<number>();
+  for (const ch of flightBitString) {
+    const n = Number(ch);
+    if (Number.isInteger(n) && n >= 1 && n <= 7) activeDays.add(n);
+  }
 
   return (
     <div className="days-of-week-strip">
       {DAY_INDEXES.map((i) => {
-        const isActive = flightBitString[i] === "1";
+        const dayNumber = i + 1;
+        const isActive = activeDays.has(dayNumber);
         const className = isActive ? "day" : "day day--inactive";
         return (
           <span
@@ -21,7 +37,7 @@ export const DaysOfWeekStrip: FC<DaysOfWeekStripProps> = ({ flightBitString }) =
             className={className}
             data-testid={`day-of-week-${i}`}
           >
-            {t(`DAYS.${i + 1}`)}
+            {t(`DAYS.${dayNumber}`)}
           </span>
         );
       })}
diff --git a/src/features/online-board/components/FlightSchedule/FlightSchedule.test.tsx b/src/features/online-board/components/FlightSchedule/FlightSchedule.test.tsx
index db547156..b2befc3f 100644
--- a/src/features/online-board/components/FlightSchedule/FlightSchedule.test.tsx
+++ b/src/features/online-board/components/FlightSchedule/FlightSchedule.test.tsx
@@ -159,10 +159,10 @@ describe("FlightSchedule", () => {
   });
 
   // TZ §4.1.16.8: uses daysOfWeek.flight (schedule days), not .current (today's active day)
-  it("uses daysOfWeek.flight bitstring for active days, not .current", () => {
-    // current = daily, flight = Mon/Wed/Fri only ("1010100")
+  it("uses daysOfWeek.flight digit-list for active days, not .current", () => {
+    // current = daily ("1234567"), flight = Mon/Wed/Fri only ("135")
     const flight = makeFlight({
-      daysOfWeek: { current: "1111111", flight: "1010100" },
+      daysOfWeek: { current: "1234567", flight: "135" },
     });
     render(<FlightSchedule flight={flight} />);
     // Mon(0), Wed(2), Fri(4) should be active