Q.Avocados And Mangos A Devastating Outlook!
Hi, the hard frost two weeks ago really scared us. As new gardeners, we read the forecasts and covered our 26 avocado trees and 5 mango trees the best we could. We used mylar aluminum sheets (like mountaineers blankets), and the green thin blankets from the big box stored. Temperature went down to 26 F. The next day, when sunny and temp reached 46, we uncovered the trees to provide sun. They looked very sad and with some damage on the tips of the leaves. Two days after, all (ALL) the leaves where brown, crepe looking, crispy feeling. No leaves fell during the next week. We are not watering nor pruning yet. We don’t know what is the best thing to do now. Carl & Kate Lake Helen, FL

Certified GKH Gardening Expert
I would have opted to cover them with burlap. They probably suffered some suffocation damage.
As long as there is still some life to the tree it will, likely, come back. Next time, you may want to leave them to the frost, or cover them with burlap. That will do much less damage than mylar will.
Here is an article that will help:
https://www.gardeningknowhow.com/plant-problems/environmental/protect-plants-in-freeze.htm
This article will help you to conduct a scratch test:
https://www.gardeningknowhow.com/ornamental/trees/tgen/tree-scratch-test.htm