diff --git a/README.md b/README.md
index 501ba68..61c3db2 100644
--- a/README.md
+++ b/README.md
@@ -559,8 +559,8 @@ with no breaking change. From `v2` the module path carries `/vN`, so fences ship
 batched into as few majors as possible.
 
 [`testdata/shipped_shape.txt`](testdata/shipped_shape.txt) pins every path, each
-category's format and the categories it reads, and each column's datatype and
-nullability; a pull request that
+template category's format, the categories each category reads, and each column's
+datatype and nullability; a pull request that
 changes it or `data/` adds its `CHANGELOG.md` entry, which CI checks. A removed,
 renamed or retyped line is a major.
 
diff --git a/release-tooling/publish_release.py b/release-tooling/publish_release.py
index 40ff3e2..313b84e 100644
--- a/release-tooling/publish_release.py
+++ b/release-tooling/publish_release.py
@@ -12,7 +12,7 @@ import sys
 import urllib.error
 import urllib.request
 
-HEADING = re.compile(r"^## \[([^\]]+)\].*?$\n(.*?)(?=^## \[|\Z)", re.M | re.S)
+HEADING = re.compile(r"^## \[([^\]]+)\].*?$\n?(.*?)(?=^## \[|\Z)", re.M | re.S)
 
 
 def request(path: str, data: dict | None = None):
@@ -45,7 +45,16 @@ def main() -> int:
 	except urllib.error.HTTPError as e:
 		if e.code != 404:
 			raise
-	release = request("releases", {"body": body, "name": tag, "tag_name": tag, "target_commitish": os.environ["SHA"]})
+	sha = os.environ["SHA"]
+	try:
+		at = request(f"tags/{tag}")["commit"]["sha"]
+		if at != sha:
+			print(f"{tag} exists at {at}, not {sha}; the version is burnt, bump the heading", file=sys.stderr)
+			return 1
+	except urllib.error.HTTPError as e:
+		if e.code != 404:
+			raise
+	release = request("releases", {"body": body, "name": tag, "tag_name": tag, "target_commitish": sha})
 	print(release["html_url"])
 	return 0
 
diff --git a/shape_test.go b/shape_test.go
index 04516d8..ca12de4 100644
--- a/shape_test.go
+++ b/shape_test.go
@@ -10,9 +10,7 @@ import (
 
 const shapePin = "testdata/shipped_shape.txt"
 
-// TestShippedShapeIsPinned pins what a version promises about the shipped data (see
-// the README's Versioning): every path, each category's format and the categories it
-// reads, and each record column's datatype and nullability. REPIN=1 rewrites the pin.
+// REPIN=1 rewrites the pin.
 func TestShippedShapeIsPinned(t *testing.T) {
 	f, err := New(WithSeed(1))
 	if err != nil {
@@ -34,9 +32,6 @@ func TestShippedShapeIsPinned(t *testing.T) {
 	}
 }
 
-// shippedShape lists every path Fake accepts, one per line. A category carries the
-// categories it references, a category-level template its format, and each of its
-// columns its datatype and whether it may be null.
 func shippedShape(f *Generator) string {
 	facts := map[string]string{}
 	var walk func(prefix string, n node)
@@ -108,10 +103,11 @@ func TestShippedShapeNamesReads(t *testing.T) {
 	f := newGenerator(t, writeData(t, map[string]string{
 		"a":     `{"format":"{x}","x":["{/b}",{"format":"{/c.v}","weight":2}]}`,
 		"b":     `"y"`,
-		"c":     `{"format":"{v}","v":["z","w"]}`,
-		"d/pos": `["{/b}","q"]`,
+		"c":     `{"format":"{v} {n}","n":[null,{"format":"{int(1,9)}","datatype":"integer"}],"v":["z","w"]}`,
+		"d/pos": `["{.q}","{/b}"]`,
+		"d/q":   `"r"`,
 	}))
-	want := "a\tformat \"{x}\"\treads b c\na.x\tstring\nb\tformat \"y\"\nc\tformat \"{v}\"\nc.v\tstring\nd.pos\treads b\n"
+	want := "a\tformat \"{x}\"\treads b c\na.x\tstring\nb\tformat \"y\"\nc\tformat \"{v} {n}\"\nc.n\tinteger null\nc.v\tstring\nd.pos\treads b d.q\nd.q\tformat \"r\"\n"
 	if got := shippedShape(f); got != want {
 		t.Fatalf("shippedShape =\n%s\nwant\n%s", got, want)
 	}