spent about 1.5 months pretty much purely dedicated to preparing for interviews for all the pre-penultimate programs (Optiver, IMC, JS, SIG, Citadel, etc). I used these resources:
Green book (Really good starter but I got bored of it after a few weeks)
EverythingQuant (Went through literally every single interview prep question, went through the interview guides, and completed the probability course just to make sure I covered all bases)
Briefly read through this guide
Watched coding Jesus in my spare time (not sure if this helped directly lmao but he’s a great creator and very informative)