Code appears to be dead for real this time...
I've rented with it a few times in the Toronto area (YYZ and some city/counter locations) and never had an issue. Now when I put it in I just get the stock retail rate as though I didn't put a code in. Also I went to My Avis to view an upcoming reservation with this code and I got an error message:
The rate code you entered requires an Avis World Wide Discount (AWD) number. Please go back and enter your AWD number or remove the rate code you entered.
So, to avoid being re-rating into unfathomable territory I'll be cancelling that reservation. Sucks though, I'm going to miss economy cars at $27.99, not to mention minivans for $45/day and luxury cars for $59 (which I never got the chance to use).