diff --git a/docs/plans/delivery-log-storage.md b/docs/plans/delivery-log-storage.md
index 1e63e91..92beec0 100644
--- a/docs/plans/delivery-log-storage.md
+++ b/docs/plans/delivery-log-storage.md
@@ -147,6 +147,6 @@ Target version cut: **`2.2.0`** (MINOR). One commit per step;
 - [x] The two texts, mockup first: the *Outbound log* help topic and the empty note (`design:` commit) — **Opus** (the help topic is in the mockups; the empty note is not drawn there - the `out-message` mockup shows a message with lines - and changes with the page)
 - [x] Message page reads the table, falls back to the current `mail.log`; help text in `help.go` — **Opus**
 - [x] [architecture.md](../architecture.md), [guide.md](../guide.md), [schema-migrations.md](../schema-migrations.md) — **Opus** (schema-migrations.md went in with the migration)
-- [ ] `go vet`, `go test`, e2e: a message's page still lists its lines after a forced rotation — **Opus**
+- [x] `go vet`, `go test`, e2e: a message's page still lists its lines after a forced rotation — **Opus** (on the test server: vet ok, 22 packages ok, e2e ok with the new step `delivery_log_survives_rotation`)
 - [ ] Technical review — **Opus**
 - [ ] Security review — **Fable**
diff --git a/docs/roadmap.md b/docs/roadmap.md
index 59ecd99..268e7b4 100644
--- a/docs/roadmap.md
+++ b/docs/roadmap.md
@@ -36,7 +36,7 @@ in `git log` and [CHANGELOG.md](../CHANGELOG.md).
 | structured-logging | `log/slog` with levels and fields | candidate | — | — |
 | review-2026-08-followups | Remaining findings of the 2026-08-19 code review | candidate | — | — |
 | panel-notifications | E-mail notifications about important events | candidate | — | — |
-| delivery-log-storage | Keep a message's `mail.log` lines with its send-log row | in progress | 5/8 | [plans/delivery-log-storage.md](plans/delivery-log-storage.md) |
+| delivery-log-storage | Keep a message's `mail.log` lines with its send-log row | in progress | 6/8 | [plans/delivery-log-storage.md](plans/delivery-log-storage.md) |
 | password-reset | Password reset by e-mail | candidate | — | — |
 | phone-desktop-mode | A phone browser in "desktop site" mode gets the phone navigation | candidate | — | — |
 | panel-redesign | Panel redesign (accepted mockups, design contract) | shipped `2.0.0` | 27/27 | [plans/panel-redesign.md](plans/panel-redesign.md) |
diff --git a/test/e2e/delivery_log_test.go b/test/e2e/delivery_log_test.go
new file mode 100644
index 0000000..b3ad200
--- /dev/null
+++ b/test/e2e/delivery_log_test.go
@@ -0,0 +1,68 @@
+package e2e
+
+import (
+	"fmt"
+	"html"
+	"regexp"
+	"strings"
+	"testing"
+	"time"
+)
+
+var sendLogDetailsRe = regexp.MustCompile(`href="(/outbound/log/\d+[^"]*)"`)
+
+// firstDeliveryPage returns the address of the page of the newest row in the
+// sender domain's send log.
+func firstDeliveryPage(sc *scenario) (string, error) {
+	rows, err := sc.panel.sendLogRows(senderDomain, "")
+	if err != nil {
+		return "", fmt.Errorf("read the send log: %w", err)
+	}
+	m := sendLogDetailsRe.FindStringSubmatch(rows)
+	if m == nil {
+		return "", fmt.Errorf("no Details link in the send log:\n%s", rows)
+	}
+	return html.UnescapeString(m[1]), nil
+}
+
+// testDeliveryLogSurvivesRotation checks that a message's page still lists
+// what Postfix wrote about it after mail.log has been rotated: the lines are
+// kept in the database by the log tailer, not searched for in the current
+// file (architecture.md § Log tailer, Stored lines). The message is the first
+// one delivered, whose page send_verify_dkim_and_status noted.
+func testDeliveryLogSurvivesRotation(t *testing.T, sc *scenario) {
+	page := sc.deliveryPage
+
+	// What the page has to show: the line that opened the queue id and the
+	// delivery line. The tailer has read both - the row is "sent" - but it
+	// writes them one at a time, so the page is polled rather than read once.
+	wanted := []string{"client=", "status=sent"}
+	shows := func() (bool, error) {
+		_, body, err := sc.panel.get(page)
+		if err != nil {
+			return false, err
+		}
+		for _, w := range wanted {
+			if !strings.Contains(body, w) {
+				return false, fmt.Errorf("%s does not show a %q line", page, w)
+			}
+		}
+		return true, nil
+	}
+	if err := waitFor("the message's page to list its log lines", 15*time.Second, 500*time.Millisecond, shows); err != nil {
+		t.Fatal(err)
+	}
+
+	if _, err := h.execIn("selfpost", "logrotate", "-f", "/etc/logrotate.d/mail"); err != nil {
+		t.Fatalf("logrotate -f: %v", err)
+	}
+	// The current file must no longer hold the delivery line, or the page
+	// finding it there would prove nothing. grep exits 1 on no match.
+	if out, err := h.execIn("selfpost", "sh", "-c", "grep -c 'status=sent' /data/log/mail.log || true"); err != nil || strings.TrimSpace(out) != "0" {
+		t.Fatalf("mail.log still holds delivery lines after the rotation (count=%q err=%v)", strings.TrimSpace(out), err)
+	}
+
+	if ok, err := shows(); !ok {
+		t.Fatalf("after mail.log was rotated: %v", err)
+	}
+}
diff --git a/test/e2e/main_test.go b/test/e2e/main_test.go
index d8f0623..a8c0071 100644
--- a/test/e2e/main_test.go
+++ b/test/e2e/main_test.go
@@ -92,6 +92,8 @@ type scenario struct {
 	l2AppPassword   string
 	clientIP        string
 	zoneRecords     []txtRecord
+	// deliveryPage is the panel page of the first delivered message.
+	deliveryPage string
 }
 
 func TestE2E(t *testing.T) {
@@ -251,6 +253,14 @@ func TestE2E(t *testing.T) {
 		}); err != nil {
 			t.Fatal(err)
 		}
+
+		// The only row so far; its page is looked at again once the log has
+		// been rotated (delivery_log_survives_rotation).
+		page, err := firstDeliveryPage(sc)
+		if err != nil {
+			t.Fatal(err)
+		}
+		sc.deliveryPage = page
 	})
 
 	run("negative_level2_ratelimit_via_panel", func(t *testing.T) {
@@ -274,6 +284,11 @@ func TestE2E(t *testing.T) {
 	run("negative_level1_ratelimit", func(t *testing.T) {
 		testLevel1RateLimit(t, sc)
 	})
+	// Rotates mail.log, so it comes after the steps that read what they need
+	// from the current file.
+	run("delivery_log_survives_rotation", func(t *testing.T) {
+		testDeliveryLogSurvivesRotation(t, sc)
+	})
 
 	// From here on the installation is no longer the one the run started: it
 	// is restored from its own backup, then switched to accept mail on port 25.