When to start submitting full time applications

I am about to start my junior year internship like many others and am wondering when I should start applying for ft positions since I already see some analyst applications opening. I'm obviously going to try and secure a ft return offer from my job this summer but want to keep my options open in case I don't get one. I am graduating in May 2025 so don't want to be too early or too late. Thanks in advance for any help.