Since my last trading update, I have made only 1 trade.
I shorted Rio Tinto yesterday (7 April). Position size was $3.2M, ended up with about $37k profit (see above).
Yesterday, the oil price reversed down sharply, bringing down all the commodities. I took advantage of that and shorted Rio Tinto. Fortunately, it paid off. I did not hold on to the position overnight as it is very volatile currently. Furthermore, the iron supply disruption is still ongoing, so it is risky to short.
On a side note, I actually lost about $45k on the same day for my long-term investing portfolio. So there was a net $8k loss for the day. My investing portfolio is negative for the year, though fortunately my trading profits are enough to more than cover the losses. I have not touched on my long-term investing because I have been much less active on the long side.