Managed money future division (hedge funds and CTAs) got extraordinarily short leading up to last week (a buy signal) (to SA this was a good time to squeeze the market back up to where they want it), plus the banking crisis (which was the impetus for the funds getting short), and the Biden admin selling SPR barrels out for the last year.
So the admin could have bought these barrels back as they said they would, but kind of balked at the deal, and SA might have been sending a signal to the market with this (true surprise) move.