My appointment is at 12:30, what time should I leave to get there ahead of the scheduled appointment if I take a cab?
[IN:GET_ESTIMATED_DEPARTURE [SL:DESTINATION [IN:GET_EVENT [SL:ATTENDEE_EVENT My ] [SL:CATEGORY_EVENT appointment ] is [SL:DATE_TIME at 12 : 30 ] ] ] , what time should I leave to get there ahead of the scheduled appointment if I take a [SL:METHOD_TRAVEL cab ] ? ]