diff --git a/amp.php b/amp.php
index 5e9d6acd192..56756588371 100644
--- a/amp.php
+++ b/amp.php
@@ -63,15 +63,6 @@ function amp_init() {
 	add_rewrite_endpoint( AMP_QUERY_VAR, EP_PERMALINK );
 	add_post_type_support( 'post', AMP_QUERY_VAR );
 
-	// Listen to post types settings.
-	$post_types_supported = AMP_Settings_Post_Types::get_instance()->get_settings_value();
-
-	foreach ( $post_types_supported as $post_type_name => $enabled ) {
-		if ( true === (bool) $enabled ) {
-			add_post_type_support( $post_type_name, AMP_QUERY_VAR );
-		}
-	}
-
 	add_filter( 'request', 'amp_force_query_var_value' );
 	add_action( 'wp', 'amp_maybe_add_actions' );
 
diff --git a/includes/amp-helper-functions.php b/includes/amp-helper-functions.php
index d9c5d86ea93..62568471a31 100644
--- a/includes/amp-helper-functions.php
+++ b/includes/amp-helper-functions.php
@@ -18,8 +18,11 @@ function amp_get_permalink( $post_id ) {
 }
 
 function post_supports_amp( $post ) {
-	// Because `add_rewrite_endpoint` doesn't let us target specific post_types :(
-	if ( ! post_type_supports( $post->post_type, AMP_QUERY_VAR ) ) {
+	// Listen to post types settings.
+	$is_enabled_via_setting = (bool) AMP_Settings_Post_Types::get_instance()->get_settings_value( $post->post_type );
+
+	// Because `add_rewrite_endpoint` doesn't let us target specific post_types.
+	if ( ! post_type_supports( $post->post_type, AMP_QUERY_VAR ) && true !== $is_enabled_via_setting ) {
 		return false;
 	}
 
diff --git a/includes/settings/class-amp-settings-post-types.php b/includes/settings/class-amp-settings-post-types.php
index 0ce2050c861..b53b6c0727b 100644
--- a/includes/settings/class-amp-settings-post-types.php
+++ b/includes/settings/class-amp-settings-post-types.php
@@ -24,13 +24,6 @@ class AMP_Settings_Post_Types {
 	 */
 	protected $setting = array();
 
-	/**
-	 * List of post types which are always AMPlified.
-	 *
-	 * @var array
-	 */
-	protected $always_on = array( 'post' );
-
 	/**
 	 * Constructor.
 	 */
@@ -73,32 +66,17 @@ public function register_settings() {
 	/**
 	 * Getter for settings value.
 	 *
-	 * The value(s) return are not sanitized.
-	 *
 	 * @param string $post_type The post type name.
-	 * @return bool|array Return true if the post type is always on; the setting value otherwise.
+	 * @return bool Return the setting value.
 	 */
-	public function get_settings_value( $post_type = false ) {
+	public function get_settings_value( $post_type ) {
 		$settings = get_option( AMP_Settings::SETTINGS_KEY, array() );
 
-		if ( false !== $post_type ) {
-			// Always return true if the post type is always on.
-			if ( true === $this->is_always_on( $post_type ) ) {
-				return true;
-			}
-
-			if ( isset( $settings[ $this->setting['id'] ][ $post_type ] ) ) {
-				return $settings[ $this->setting['id'] ][ $post_type ];
-			}
-
-			return false;
+		if ( isset( $settings[ $this->setting['id'] ][ $post_type ] ) ) {
+			return (bool) $settings[ $this->setting['id'] ][ $post_type ];
 		}
 
-		if ( empty( $settings[ $this->setting['id'] ] ) || ! is_array( $settings[ $this->setting['id'] ] ) ) {
-			return array();
-		}
-
-		return $settings[ $this->setting['id'] ];
+		return false;
 	}
 
 	/**
@@ -130,16 +108,6 @@ public function get_setting_name( $post_type ) {
 		return AMP_Settings::SETTINGS_KEY . "[{$id}][{$post_type}]";
 	}
 
-	/**
-	 * Check if a post type is always on.
-	 *
-	 * @param string $post_type The post type name.
-	 * @return bool True if the post type is always on; false otherwise.
-	 */
-	public function is_always_on( $post_type ) {
-		return in_array( $post_type, $this->always_on, true );
-	}
-
 	/**
 	 * Setting renderer.
 	 */
diff --git a/templates/admin/settings/fields/checkbox-post-types.php b/templates/admin/settings/fields/checkbox-post-types.php
index 0bc1d8c0dde..e34166eb0ff 100644
--- a/templates/admin/settings/fields/checkbox-post-types.php
+++ b/templates/admin/settings/fields/checkbox-post-types.php
@@ -13,7 +13,7 @@
 <fieldset>
 	<?php foreach ( $this->get_supported_post_types() as $post_type ) : ?>
 		<label>
-			<input type="checkbox" value="1" name="<?php echo esc_attr( $this->get_setting_name( $post_type->name ) ); ?>"<?php checked( true, (bool) $this->get_settings_value( $post_type->name ) ); ?><?php disabled( true, $this->is_always_on( $post_type->name ) ); ?>> <?php echo esc_html( $post_type->label ); ?>
+			<input type="checkbox" value="1" name="<?php echo esc_attr( $this->get_setting_name( $post_type->name ) ); ?>"<?php checked( true, (bool) $this->get_settings_value( $post_type->name ) || post_type_supports( $post_type->name, AMP_QUERY_VAR ) ); ?><?php disabled( true, post_type_supports( $post_type->name, AMP_QUERY_VAR ) ); ?>> <?php echo esc_html( $post_type->label ); ?>
 		</label>
 		<br>
 	<?php endforeach; ?>
diff --git a/tests/test-class-amp-settings-post-types.php b/tests/test-class-amp-settings-post-types.php
index c4f25b0112e..725c334fdaa 100644
--- a/tests/test-class-amp-settings-post-types.php
+++ b/tests/test-class-amp-settings-post-types.php
@@ -80,8 +80,6 @@ public function test_register_settings() {
 	 * @see AMP_Settings_Post_Types::get_settings_value()
 	 */
 	public function test_get_settings_value() {
-		$this->assertEmpty( $this->instance->get_settings_value() );
-		$this->assertInternalType( 'array', $this->instance->get_settings_value() );
 		$this->assertFalse( $this->instance->get_settings_value( 'foo' ) );
 
 		update_option( AMP_Settings::SETTINGS_KEY, array(
@@ -90,8 +88,6 @@ public function test_get_settings_value() {
 			),
 		) );
 
-		$this->assertContains( 'post', $this->instance->get_settings_value() );
-		$this->assertInternalType( 'array', $this->instance->get_settings_value() );
 		$this->assertTrue( $this->instance->get_settings_value( 'post' ) );
 
 		// Cleanup.
@@ -117,15 +113,6 @@ public function test_get_setting_name() {
 		$this->assertEquals( AMP_Settings::SETTINGS_KEY . '[post_types_support][post]', $this->instance->get_setting_name( 'post' ) );
 	}
 
-	/**
-	 * Test is_always_on.
-	 *
-	 * @see AMP_Settings_Post_Types::is_always_on()
-	 */
-	public function test_is_always_on() {
-		$this->assertTrue( $this->instance->is_always_on( 'post' ) );
-	}
-
 	/**
 	 * Test render_setting.
 	 *