Previewed at WWDC, launching in the fall.
Apple Preparing to Launch 128 GB Versions of Full-Size iPad?
While the exact identity of the devices is not revealed in the stock database, they do appear as "ultimate" configurations of the current full-size iPad models, suggesting that they may represent 128 GB models of the Wi-Fi and Wi-Fi + Cellular iPad in both black and white.
While it is certainly plausible that this new iPad model is the 128GB iPad, we are currently not confident enough to outright claim that, but it seems likely based on the evidence. [..]No additional information such as specifications, price, or a launch date for the new configurations have yet been revealed.
The P101 and P103 names are Apple’s internal nomenclature for the WiFi-only and Cellular-compatible fourth-generation iPads, respectively. Both of those models comes in 16GB, 32GB, and 64GB configurations. These storage sizes are known as “GOOD,” “BETTER,” and “BEST,” respectively. As you can see in our table above, Apple is preparing to release the additional “ULTIMATE” model. “ULTIMATE” frequently refers to the most premium or highest capacity model available. The “A” points to a black configuration, and “B” stands for the white option.