diff --git a/src/Formatter/GBFormatter.php b/src/Formatter/GBFormatter.php
index 14035db..6d63c87 100644
--- a/src/Formatter/GBFormatter.php
+++ b/src/Formatter/GBFormatter.php
@@ -103,7 +103,7 @@ private function getPatterns() : array
         $alphaOut4 = '[ABEHMNPRVWXY]';
 
         // inward code alpha chars
-        $alphaIn = '[ABDEFGHJLNPQRSTUWXYZ]';
+        $alphaIn = '[ABCDEFGHJLNPQRSTUWXYZ]';
 
         $outPatterns = [];
 
diff --git a/tests/Formatter/GBFormatterTest.php b/tests/Formatter/GBFormatterTest.php
index fd90bae..986e3c7 100644
--- a/tests/Formatter/GBFormatterTest.php
+++ b/tests/Formatter/GBFormatterTest.php
@@ -153,7 +153,7 @@ public function providerFormat() : array
             ['AB1234', null],
             ['AB123C', null],
             ['AB12C3', null],
-            ['AB12CD', null],
+            ['AB12CD', 'AB1 2CD'],
             ['AB12DD', 'AB1 2DD'],
             ['AB1C23', null],
             ['AB1C2D', null],
@@ -267,7 +267,7 @@ public function providerFormat() : array
             ['AB12345', null],
             ['AB1234C', null],
             ['AB123C4', null],
-            ['AB123CD', null],
+            ['AB123CD', 'AB12 3CD'],
             ['AB123DD', 'AB12 3DD'],
             ['AB12C34', null],
             ['AB12C3D', null],