hsd-ids-filter.php

<?php
add_filter( 'hsd_get_user_customer_ids', 'check_hsd_customer_id', 999, 2 );
check_hsd_customer_id( $hsd_ids, $user_id ) {

  if ( $hsd_ids ) {

    $now = current_time( 'timestamp' );
    $last_sync = get_user_meta( $user_id, 'pp_hsd_last_sync', true );
    if ( ! $last_sync || $last_sync <= ( $now - ( HOUR_IN_SECONDS * 6 ) ) ) {

      update_user_meta( $user_id, 'pp_hsd_last_sync', $now );
      foreach ( $hsd_ids as $i => $id ) {

        $req = HelpScout_API::api_request( 'customers/' . $id );
        $res = json_decode( $req );
        if ( $res && isset( $res->code ) && 404 === $res->code ) {

          unset( $hsd_ids[ $i ] );

        }

      }

    }


  }

  return $hsd_ids;

}