private static function can_process( $type, $user_id, $template_id, $related_id = '', $engagement_id = null ) {

		/**
		 * Skip engagement processing checks and force engagements to process.
		 *
		 * This filter is used internally to skip running checks for immediate engagements which cannot
		 * suffer from the issues that these checks seek to avoid.
		 *
		 * @since 6.0.0
		 *
		 * @param boolean  $skip_checks   Whether or not to skip checks.
		 * @param string   $type          The engagement type, either "achievement" or "certificate".
		 * @param int      $user_id       WP_User ID of the student earning the engagement.
		 * @param int      $template_id   WP_Post ID of the template post (llms_achievement or llms_certificate).
		 * @param string   $related_id    WP_Post ID of the triggering related post (course, lesson, etc...) or an empty string for user registration.
		 * @param null|int $engagement_id WP_Post ID of the engagement post used to configure the trigger. A `null` value maybe be passed for legacy
		 *                                delayed engagements which were created without an engagement ID or when manually awarding via the admin UI.
		 * }
		 */
		$skip_checks = apply_filters( 'llms_skip_engagement_processing_checks', false, $type, $user_id, $template_id, $related_id, $engagement_id );
		if ( $skip_checks ) {
			return true;
		}

		$checks = array();

		// User must exist.
		$user_check = get_userdata( $user_id ) ? true : new WP_Error( 'llms-engagement-check-user--not-found', sprintf( __( 'User "%d" not found.', 'lifterlms' ), $user_id ) );
		$checks[]   = $user_check;

		// Template must be published and of the expected post type.
		$checks[] = self::check_post( $template_id, "llms_{$type}" );

		// Check related post (if one is passed).
		if ( ! empty( $related_id ) ) {
			$check_related = self::check_post( $related_id );
			$checks[]      = $check_related;
			// Check post enrollment if the check passed and there's no user issues.
			if ( ! is_wp_error( $check_related ) && ! is_wp_error( $user_check ) ) {
				$checks[] = self::check_post_enrollment( $related_id, $user_id );
			}
		}

		// Ensure we have an argument to check, engagements created prior to v6.0.0 will not have this argument.
		if ( ! empty( $engagement_id ) ) {
			$checks[] = self::check_post( $engagement_id, 'llms_engagement' );
		}

		// Find all the failed checks.
		$errors = array_values( array_filter( $checks, 'is_wp_error' ) );

		/**
		 * Filters whether or not an engagement should be processed immediately prior to it being sent or awarded.
		 *
		 * The dynamic portion of this hook, `{$type}` refers to the type of engagement being processed, either "email",
		 * "certificate", or "achievement".
		 *
		 * @since 6.0.0
		 *
		 * @param boolean|WP_Error[] $can_process   An array of WP_Errors or true if the engagement can be processed.
		 * @param int                $user_id       WP_User ID of the student earning the engagement.
		 * @param int                $template_id   WP_Post ID of the template post (llms_achievement or llms_certificate).
		 * @param string             $related_id    WP_Post ID of the triggering related post (course, lesson, etc...) or an empty string for user registration.
		 * @param null|int           $engagement_id WP_Post ID of the engagement post used to configure the trigger. A `null` value maybe be passed for legacy
		 *                                          delayed engagements which were created without an engagement ID or when manually awarding via the admin UI.
		 * }
		 */
		return apply_filters( "llms_proccess_{$type}_engagement", count( $errors ) ? $errors : true, $user_id, $template_id, $related_id, $engagement_id );

	}