15. On the user’s first visit to this service's WAYF page, a cookie is dropped on the user’s machine with the entityID of the IdP they selected. Subsequently, the WAYF will look for this cookie and automatically redirect the user to their IdP if it is found, so in some respects it acts like a WAYFless URL. The URL is generated dynamically from the last refresh of the online metadata, so any change in the URL of the IdP or SP authentication points should be picked up automatically.