code: public function findChanged(DateTimeImmutable $startTimestamp)
      {
          $elements = iterator_to_array($this->client->getIterator('categories', [
              'with' => 'details,clients',
              'type' => 'item',
              'updatedAt' => $startTimestamp->format(DATE_W3C),
              'lang' => $this->languageHelper->getLanguagesQueryString(),
          ]));
  
          $this->sortCategories($elements);
  
          return $elements;
      }
docs: @param DateTimeImmutable $startTimestamp
  
  @return array