(5)In order to ensure equal treatment in the Union, it should be specified what would constitute a ‘reasonable period’ for an issuer of asset-referenced tokens to communicate the outcome of its investigations. The issuer should keep the complainant informed about the progress of the complaints-handling procedure and provide a response without undue delay and in any event within the time limits set at national level to address complaints filed by complainants, where applicable. The issuer should assess all complaints, identifying shortcomings that may be recurring.