Warnings on a certain date
 

Hi,

I'm creating a spreadsheet at work which needs to alert me when a lease on a property is coming to an end. I need, ideally, a yellow or orange reminder 12 months before the final day and then a red one 3 months after that one (9months before the final day).

I've played around with conditional formatting until I'm blue in the face but to no avail! Any idea if this is even possible?

Thanks!