On Sept. 28, CellCog’s account reported that Kling 4.0 Flash became available to Ultra Yearly subscribers, while the broader Kling 4.0 rollout is planned for October without a specific date.
The early details suggest a larger jump in video control than a routine access update. CellCog says Kling 4.0 supports native generation up to 30 seconds, up to 10 keyframes in one clip, and as many as 15 multimodal inputs through Omni Reference.
What is live now, though, is still a limited-access release rather than a full production launch. As of Sept. 28, Kling had not published public API model IDs, API pricing, or benchmark data in the sources reviewed.
For automation teams, that means waiting before treating this as production-ready. The feature set could help with longer-form video workflows and tighter shot steering, but there still is not enough public API detail to wire it into stable pipelines with confidence.
One caveat remains unresolved: CellCog ties the Sept. 28 announcement to output up to 4K with 10-bit HDR, while earlier leak-based coverage described lower preview settings. Until broader access lands, those output specs should be treated as provisional.