diff --git a/TODO.md b/TODO.md
index 967a392..5e5fc5e 100644
--- a/TODO.md
+++ b/TODO.md
@@ -150,7 +150,11 @@ saint has the same kind of mismatch.
   James the Greater], Louis, Zephyrinus, Augustine), 2 already correct as
   found (Finding of St. Stephen, the Decollation of St. John the Baptist
   — both plain unmodified matches against the live query, no fix needed).
-- **September-December (29 saints): not started.**
+- **September (5 total): done, all 5.** 1 corrected (Nativity of the BVM),
+  4 authored fresh (Matthew [reworded English, same fix as Matthias/
+  Barnabas/James the Greater/Bartholomew], Ss. Cyprian and Justina,
+  Ss. Cosmas and Damian, Jerome).
+- **October-December (24 saints): not started.**
 - **~52 temporal entries: not started.**
 - **94 `propers: null` saints: not started** — need a collect authored (a
   bigger, separate task) before an antiphon id even has anywhere to attach.
diff --git a/src/data/propers/common/nativity-bvm-antiphon.yml b/src/data/propers/common/nativity-bvm-antiphon.yml
index 8b362d7..9408d16 100644
--- a/src/data/propers/common/nativity-bvm-antiphon.yml
+++ b/src/data/propers/common/nativity-bvm-antiphon.yml
@@ -1,12 +1,14 @@
-# Verified against Divinum Officium (Latin/English Sancti/09-08.txt's own
-# [Ant 1] — the Lauds-hour antiphon, not Terce's. That file's own
-# "(rubrica cisterciensis)" alternate is a different text entirely; the
-# plain default is used here for consistency with every other saint file
-# in this set.
+# Verified against Divinum Officium (Monastic Tridentinum 1617), Lauds
+# live query, the Nativity of the Blessed Virgin Mary's own day
+# (2026-09-08) -- the Benedictus antiphon. Corrects the previous version
+# of this file, which had been sourced from the Roman/secular rite's
+# Sancti/09-08.txt's own [Ant 1] instead: real but different text from
+# what Monastic 1617 actually renders at Lauds, same mistake as
+# St. Lawrence's earlier fix.
 id: nativity-bvm-antiphon
 text:
-  la: "Gloriósæ * Vírginis Maríæ ortum digníssimum recolámus, quæ et Genitrícis dignitátem obtínuit, et virginálem pudicítiam non amísit."
-  en: "Let us tell again * of the right worthy Birth of the glorious Virgin Mary, who gained the honour of Motherhood without losing the guilelessness of a Maid."
+  la: "Nativitátem hodiérnam perpétuæ Vírginis Genitrícis Dei Maríæ solémniter celebrémus, qua celsitúdo throni procéssit, allelúja."
+  en: "Let us this day keep solemnly the Birthday of Mary, Mother but still Maiden, her Birth, a step toward the loftiness of her throne. Alleluia."
 status:
   la: verified
   en: verified
diff --git a/src/data/propers/common/ss-cosmas-and-damian-antiphon.yml b/src/data/propers/common/ss-cosmas-and-damian-antiphon.yml
new file mode 100644
index 0000000..c532c3f
--- /dev/null
+++ b/src/data/propers/common/ss-cosmas-and-damian-antiphon.yml
@@ -0,0 +1,10 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617), Lauds
+# live query, Ss. Cosmas and Damian's own day (2027-09-27 -- 2026 is an
+# ordinary Sunday). The Benedictus antiphon.
+id: ss-cosmas-and-damian-antiphon
+text:
+  la: "Vestri capílli cápitis * omnes numeráti sunt: nolíte timére: multis passéribus melióres estis vos."
+  en: "Even the very hairs of your head are all numbered: * fear not therefore; ye are of more value than many sparrows."
+status:
+  la: verified
+  en: verified
diff --git a/src/data/propers/common/ss-cyprian-and-justina-antiphon.yml b/src/data/propers/common/ss-cyprian-and-justina-antiphon.yml
new file mode 100644
index 0000000..425efaa
--- /dev/null
+++ b/src/data/propers/common/ss-cyprian-and-justina-antiphon.yml
@@ -0,0 +1,11 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617), Lauds
+# live query, Ss. Cyprian and Justina's own day (2028-09-26 -- 2026/2027
+# are Our Lady's Saturday / an ordinary Sunday respectively). The
+# Benedictus antiphon.
+id: ss-cyprian-and-justina-antiphon
+text:
+  la: "Vestri capílli cápitis * omnes numeráti sunt: nolíte timére: multis passéribus melióres estis vos."
+  en: "Even the very hairs of your head are all numbered: * fear not therefore; ye are of more value than many sparrows."
+status:
+  la: verified
+  en: verified
diff --git a/src/data/propers/common/st-jerome-antiphon.yml b/src/data/propers/common/st-jerome-antiphon.yml
new file mode 100644
index 0000000..bf35a7f
--- /dev/null
+++ b/src/data/propers/common/st-jerome-antiphon.yml
@@ -0,0 +1,9 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617), Lauds
+# live query, St. Jerome's own day (2026-09-30). The Benedictus antiphon.
+id: st-jerome-antiphon
+text:
+  la: "Euge, serve bone et fidélis, quia in pauca fuísti fidélis, supra multa te constítuam, intra in gáudium Dómini tui."
+  en: "Well done, thou good and faithful servant; thou hast been faithful over a few things, I will make thee ruler over many things; enter thou into the joy of thy Lord."
+status:
+  la: verified
+  en: verified
diff --git a/src/data/propers/common/st-matthew-antiphon.yml b/src/data/propers/common/st-matthew-antiphon.yml
new file mode 100644
index 0000000..cdaed4e
--- /dev/null
+++ b/src/data/propers/common/st-matthew-antiphon.yml
@@ -0,0 +1,15 @@
+# Verified against Divinum Officium (Monastic Tridentinum 1617), Lauds
+# live query, St. Matthew's own day (2026-09-21) -- the Benedictus
+# antiphon (Matt 19:27ff, same verse as St. Matthias/St. Barnabas/
+# St. James the Greater/St. Bartholomew's own). The source's own English
+# existed but was jarringly modern next to every other antiphon's archaic
+# register -- reworded to match (the underlying verse's standard
+# Douay-Rheims wording, same fix as those four), marked draft rather
+# than a straight source transcription.
+id: st-matthew-antiphon
+text:
+  la: "Vos qui reliquístis ómnia, et secúti estis me, céntuplum accipiétis, et vitam ætérnam possidébitis."
+  en: "Ye who have left all things, and have followed me, shall receive an hundredfold, and shall possess life everlasting."
+status:
+  la: verified
+  en: draft