Making a Baklava cheesecake recipe where the top is completely covered by phyllo sheets (so I cant see the cheesecake), converting the recipe from an 8 inch to a 6inch, how do I check for doneness/how long to bake?

Recipe link https://www.instagram.com/reel/CpxPBMwIazZ/?igsh=MTVkdnlwb2trOXk5OQ== It's described as being baked at 320F for atleast 1 hour and 30 mins (with a 20 minute rest in the oven), I want to make it 6 inch so by how much should I cut the baking time? Thanks submitted by /u/dedededestroyer