It is a big improvement. So congratulation on your accomplishment. However, honestly speaking, 20AA is national average for accepted applicants, so it won't give you much advantage. 19PAT might actually be below average.
I had 20AA/22PAT and it helped me get several interviews, but only got me as far as waitlisting, no acceptance due to my below average GPA. I took a master program, got 3.8GPA, reapplied with the same DAT and got accepted. So, an average DAT won't keep you out if you have a good GPA to make your app more competitive. Best of luck.