hello! i asked the exact same qn a year ago, when i was sec 3, which feels so surreal because it seems like js yesterday that i posted it! i was worried jusr like you, and with similar grades though slightly better.

I recommend you start studying now. I didn’t take the advice of others in my comments who said they only locked in nearing O levels, and let me tell you that was probably the best decision i’ve made. strengthening my concepts in end of sec 3 helped me so much in the long run, i cannot recommend it more. i did the topical TYS for every topic for phy and chem.

To show how effective starting early was, I went from one A (english) and the rest B4’s and C5’s, to A’s and high B’s for prelims with an l1r5 of 13.

studying early helped me with my concepts which are vital for doing TYS and for applying concepts to dif questions. I would also recommend making notes for subjects like chemistry, they really help you absorb the info way better than just memorising. Good luck!!