diff --git a/main.go b/main.go
index 029be3b..7715e35 100644
--- a/main.go
+++ b/main.go
@@ -16,7 +16,7 @@ import (
 
 func main() {
 	// Prepare regexp templates.
-	rxHeader := regexp.MustCompile(`^(\[\#[0-9Xx]+\]\s|Release|Revert|Reapply)`)
+	rxHeader := regexp.MustCompile(`^(\[\#[0-9]+\]\s|Release|Revert|Reapply)`)
 	rxSignOff := regexp.MustCompile(`^Signed-off-by:`)
 
 	// Open current git dir.