Troubleshooting Help – Spatchcocked Roast Chicken

This is my most recent go at this recipe: https://www.seriouseats.com/butterflied-roasted-chicken-with-quick-jus-recipe

The issue I’m having is with getting the skin to brown evenly and crisp up. The skin each time has come out unevenly brown and not very crispy. Especially on the legs, the skin just feels very smooth?

For the bird pictured, here was my process:

– poked several holes in the fat deposits

– sprinkled 1tbsp Diamond Crystal kosher salt + 1tsp baking powder mixture all over the skin

– left uncovered in the fridge on a wire rack in a sheet pan for 20 hours

– rested at room temperature for 1 hour prior to roasting

– removed any excess moisture with a paper towel (there wasn’t much after 20 hours)

– coated all of the skin generously with olive oil

– roasted at 425F with convection on, middle rack, legs facing the back of the oven. Rotated to have legs facing the front for the last 10 minutes of roasting in hopes that would crisp the leg skin

– roasted for roughly 45-50 minutes. Picture was taken about 5 minutes after removing from the oven. Did not tent with foil after removing

Here’s what I didn’t do:

– did not use any black pepper or other seasonings than salt. I’ve been trying to nail a simple salted roast chicken before adding other elements

– did not separate the breast skin from the meat

Any guidance would be so appreciated! It’s a very basic recipe and other people have such great results, so I’m determined to get it right.