The "13 Ultra" is currently depicted as reprising the massive round central camera hump of its alleged predecessor, the 12S Ultra, albeit possibly slightly cleaner and with a larger central lens this time around.
This potential iterative design upgrade has also now allegedly started to appear on IMEI databases, thus suggesting that it is lndeed on its way to a launch. Xiaomiui claims to have spotted the 13 Ultra thereon as the 2304FPN6DC for China, or 2304FPN6DG for the rest of the world.
However, according to another leaker, WHYLAB, this does not include India. Accordingly, there may be a third model number (which would be 2304FPN6DI) on the way - or Xiaomi has no intentions of releasing its next-gen Ultra in that county at all.
Meanwhile, Xiaomiui also now claims to have figured out the exact build of MIUI the 13 Ultra will boot out of the box, based on its alleged code-name: ishtar.
Again, the version number allegedly varies between Chinese and international units: 22.11.5 (for the device ishtar_pre) and 22.11.28 (ishtar_pre_global) respectively.