Samsung’s next premium tablet line is moving from planning to proof-of-life: firmware has now surfaced for a device believed to be the Galaxy Tab S12 Ultra, suggesting the company has started internal testing. The Galaxy Tab S12 firmware testing leak doesn’t show off hardware, but it does point to the kind of behind-the-scenes work that usually shows up before a launch window gets serious.
Firmware for model X946B has appeared
The firmware spotted on Samsung’s server carries the build number X946BXXU0AZDN and is tied to model X946B. Previous reporting links that model to the Galaxy Tab S12 Ultra, which is enough to suggest the tablet has entered an early testing phase. That’s not a launch date, but it is the sort of breadcrumb Samsung tends to leave before a new flagship quietly starts taking shape.
There’s no new hardware detail here, which is mildly frustrating and entirely on brand for pre-release leaks. Still, firmware testing usually means the company is getting closer to freezing software choices, and that matters because tablet launches live or die on timing as much as on specs.
What is known about the Galaxy Tab S12 series
So far, the Galaxy Tab S12 family is expected to include the Galaxy Tab S12+ and the Galaxy Tab S12 Ultra. The only specification tied to the series right now is a battery claim for the Galaxy Tab S12+, which is said to use a 10,392mAh cell that Samsung may market as 10,500mAh.
- Galaxy Tab S12+ battery: 10,392mAh, possibly advertised as 10,500mAh
- Model spotted in firmware: X946B
- Reported build version: X946BXXU0AZDN
A September debut is the obvious bet
Samsung launched the Galaxy Tab S11 lineup in September 2025, and the company usually sticks to a yearly refresh cycle for its flagship tablets. That makes September 2026 the most plausible launch window for the Galaxy Tab S12 series, even if Samsung is not saying so yet. The bigger question is whether the next round is a meaningful upgrade or just a polished rerun with a larger battery label and a new model number.