Here are a couple things I've learned over the past year.
1. CRCL ("can't raise can't leave") theory was debunked. We might never know why they didn't raise at $350 but I think they could have if they really wanted to. I'm guessing Tesla overestimated their TAM and Q1 sales falling off a cliff really caught them by surprise. My theory is that Musk thought they had more time and was trying to get the converts in the money by squeezing shorts, and a raise would have put that at risk. The mistake was making a conclusion (can't raise) based on the assumption that Musk wouldn't put the company at risk by not raising if he could. He had already demonstrated the extent of his hubris and irrationality before, so in hindsight this was an unsafe assumption. Short stock and high strike puts worked well. OTM bankruptcy puts got killed.
2. If you have 70% q/q revenue growth and negative working capital, your FCF will look amazing. And vice versa when your sales drop. Bears saw the big spike in sales coming but didn't make the connection to FCF, still projecting high cash burn in Q3. Knowing this, shorts could have spared a few months of pain and pressed the short in Q1.