Cannot add date to a drill down

I have a line chart where in color I have three variables to drill from. I wanted to add two more, being two levels of a date (month and week), but it’s doesn’t allow me to do anything but replace the variables already there. If I try to do it with a string variable it allows me to add and to replace but it doesn’t work with date variables. I have also tried remove all variables and once I add the date aggregated by month it does not allow me to add the same variable again aggregated by week or any other variable. Is this expected behaviour? Any way to workaround this?

Date drill-down is automatically available your field is properly configured as date. Click inside the visual on any data-point to drill up-down based on the date field.
Date Drill Down

Still, I can’t add the date field if other fields are present, it is only the date or only field which are not dates. Is this the expected behaviour?

Hugo, your first three variables, is one of them already a date field, having the calendar icon next to it in the visualization panel?

Yes Hugo, you are right. When you add a date field, you cannot add any more fields to the same fieldwell as a drill down.