I think there are two method to do that symbology
Frist method ( recommended 😞
1- Add New field to your attribute table .
2- Select by attribute for records that "date is over 1 year ago" / "within 1 year" / Null
3- Calculate new field with unique value for each selection.
4-Use that field in symbology.
Second method:
1- Add your layer in TOC 3 times
2- Make a definition query for each layer with unique group as you want "date is over 1 year ago" / "within 1 year" / Null
(each layer has different expression)
3- Symbolize each layer manual.