It seems SF600 Gold was out of stock for a long time in several locations (as reported by some members here). Locally, it was not available from December last year to April. Then, it came back on stock in early May. Since then, I have seen it available in all my local stores.
I expect, SF600 Platinum will be available when this current stock of SF600 Gold runs out. If the SF600 Platinum is available now, I think no one will buy the SF600 Gold and the current inventory will have to be returned. So, both Corsair and retail channels want to clear out this 'final' batch of SF600 Gold.
The fact that SF600 Gold was restocked in May might mean that Corsair is not ready to release a huge supply of SF600 Plantium. Or else, the shortage of SF600 will continue from May onward to now and Corsair will release a huge supply of SF600 Platinum right after Computex. But it appears it is not happening. So, right now, factories are busy manufacturing piles of SF600 Platinum while SF600 Gold are being cleared out. My guess, a period of 3-4 month?
BTW, I now have a new SF600 Gold, as the benefit of Father's Day! I will not do the building until Q4 though. Hopefully, by that time, 8-core '8700K' will be released. And, I just read that Asus is going to release eight Z390 based motherboards, which include the m-ITX Z390-I Gaming. (
https://videocardz.com/newz/asus-to-introduce-rog-maximus-xi-series-for-z390-chipset)