ZL is horrible at supply management. They might be in stock tomorrow, or they might be in stock in several months, or never. If you don't care if/when you get the light, then just wait a few months and see. If you want a new light anytime soon, try a different brand.
My suspicion is that they're updating the SC52 models, and we'll see something new sometime in the next few months.
If it wasn't for their unique UI, I'd give up on ZL. Let's face it: they're ugly lights, there's been questionable quality in terms of water resistance and tint problems, and complaints of dealing with customer service in China. But, they are very innovative lights, so some people (including myself) have put up with the downsides.