diff --git a/mu-plugins/blocks/notice/index.php b/mu-plugins/blocks/notice/index.php
index 5181b8fc..a5b9bb42 100644
--- a/mu-plugins/blocks/notice/index.php
+++ b/mu-plugins/blocks/notice/index.php
@@ -23,21 +23,18 @@ function init() {
 
 	foreach ( [ 'info', 'tip', 'alert', 'tutorial', 'warning' ] as $shortcode ) {
 		remove_shortcode( $shortcode );
-		add_shortcode( $shortcode, __NAMESPACE__ . '\render_callout_as_notice' );
+		add_shortcode( $shortcode, __NAMESPACE__ . '\render_shortcode' );
 	}
 }
 
 /**
- * Display a callout using the notice block.
+ * Maps a callout type to a notice type.
  *
- * @param array|string $attr    Callout shortcode attributes array or empty string.
- * @param string       $content Callout content.
- * @param string       $tag     Callout type.
- *
- * @return string Callout output as HTML markup.
+ * @param string $type The callout type.
+ * @return string The corresponding notice type.
  */
-function render_callout_as_notice( $attr, $content, $tag ) {
-	$shortcode_mapping = array(
+function map_type( $type ) {
+	$mapping = array(
 		'info'     => 'info',
 		'tip'      => 'tip',
 		'alert'    => 'alert',
@@ -45,15 +42,17 @@ function render_callout_as_notice( $attr, $content, $tag ) {
 		'warning'  => 'warning',
 	);
 
-	$type = $shortcode_mapping[ $tag ] ?: 'tip';
-
-	// Sanitize message content.
-	$content = wp_kses_post( $content );
-	// Temporarily disable o2 processing while formatting content.
-	add_filter( 'o2_process_the_content', '__return_false', 1 );
-	$content = apply_filters( 'the_content', $content );
-	remove_filter( 'o2_process_the_content', '__return_false', 1 );
+	return $mapping[ $type ] ?: 'tip';
+}
 
+/**
+ * Generates and processes block markup for a notice.
+ *
+ * @param string $type The notice type.
+ * @param string $content The content to insert into the block.
+ * @return string The processed block markup.
+ */
+function generate_notice_block_markup( $type, $content ) {
 	// Create a unique placeholder for the content.
 	// Directly processing `$content` with `do_blocks` can lead to buggy layouts on make.wp.org.
 	// See https://github.com/WordPress/wporg-mu-plugins/pull/337#issuecomment-1819992059.
@@ -68,13 +67,33 @@ function render_callout_as_notice( $attr, $content, $tag ) {
 EOT;
 
 	$processed_markup = do_blocks( $block_markup );
-	$final_markup = str_replace( $placeholder, $content, $processed_markup );
+	return str_replace( $placeholder, $content, $processed_markup );
+}
 
-	return $final_markup;
+/**
+ * Display the callout shortcodes using the notice block.
+ *
+ * @param array|string $attr    Shortcode attributes array or empty string.
+ * @param string       $content Shortcode content.
+ * @param string       $tag     Shortcode name.
+ *
+ * @return string Shortcode output as HTML markup.
+ */
+function render_shortcode( $attr, $content, $tag ) {
+	$type = map_type( $tag );
+
+	// Sanitize message content.
+	$content = wp_kses_post( $content );
+	// Temporarily disable o2 processing while formatting content.
+	add_filter( 'o2_process_the_content', '__return_false', 1 );
+	$content = apply_filters( 'the_content', $content );
+	remove_filter( 'o2_process_the_content', '__return_false', 1 );
+
+	return generate_notice_block_markup( $type, $content );
 }
 
 /**
- * Renders a callout block as a notice.
+ * Renders a callout block as a notice block.
  *
  * @param string|null $pre_render The pre-rendered content or null.
  * @param array       $parsed_block The parsed block array.
@@ -89,11 +108,14 @@ function render_callout_block_as_notice( $pre_render, $parsed_block ) {
 	// Extract the specific "callout-*" class and remove the "callout-" prefix
 	preg_match( '/\bcallout-([\w-]+)\b/', $callout_wrapper, $matches );
 	$tag = $matches[1] ?? 'tip';
+	$type = map_type( $tag );
 
 	$content = '';
 	foreach ( $parsed_block['innerBlocks'] as $inner_block ) {
 		$content .= render_block( $inner_block );
 	}
+	// Sanitize message content.
+	$content = wp_kses_post( $content );
 
-	return render_callout_as_notice( '', $content, $tag );
+	return generate_notice_block_markup( $type, $content );
 }