The temperature controlled timing advance is done by another set of points in the distributor.  If you have that system it might be that one set of points needs adjustment.  Have you been under the distributor cap recently?

6 hours ago, jonbill said:

can you describe what you've got in a bit more detail @jas. you've mentioned EGR and water temp switch, neither of which I'd expect on a 72 carb car. 

Good point. The EGR was first seen on the 73.