Do the age symbology options in arcgis online update with the addition of new dates or are they static? We want to have one symbol for features less than 30 days old from the current date and another symbol for features more than 30 days old.
When using the Age option when styling time, you can calculate this time based on a specific date field in your data or you can select a specific date from a drop down: Style time—ArcGIS Online Help | ArcGIS
