Apple quietly updated Mac Studio configuration options this week, removing the 512GB memory upgrade. As of yesterday, there is no option to purchase a Mac Studio with 512GB RAM, with the machine now maxing out at 256GB. The Mac Studio starts with 36GB RAM, but there were upgrades ranging from 48GB to 512GB, with the higher tier upgrades limited to the M3 Ultra chip. Now there are options ranging from 48GB to 256GB, with wait times into May for the 256GB upgrade.
But … it’s Apple. Apple product buyers are used to being gouged out the arse for money.
I’ll bet this option just wasn’t selling and so Apple quietly discontinued it.