just to wrap up, I heard back from the company secretary and it seems my interpretation was correct (although the daily VWAP will be a 10-day VWAP):
"...anytime from 6 months after appointment and three years from now the performance rights vest if the VWAP (this will be a 10-day VWAP) exceeds 34c (tranche 1), 40c (tranche 2), and 44c (tranche 3)"
AVZ Price at posting:
29.5¢ Sentiment: Hold Disclosure: Held