Do we know any specifics of Type 346/A/B?
Very little actually. The original assessment in the 2000s leaned on it being a C-band AESA radar.
A few years ago a Wikipedia article emerged, claiming that it's a dual S-band/C-band radar with over 5000 T/R elements, with about 25W peak power per S-band transmitter.
Measurements done by some people on SDF/CDF lead to the conclusion that the outer radar panel area is significantly larger than that of the SPY-1 (roughly 4x4m octagon).
My own measurements of the radar superstructure opening for the Type 055 fitting out in Dalian showed 5.1x4.8 meters.
There are some photos of the Type 346 radar array installed on the Type 052D showing a central circular layout with two horizontal rectangular arrays above and below the circle. Some have conjectured these to be the C-band arrays mentioned in the Wikipedia article. My own assessment is that the likelihood of those being C-band FCR arrays is very low, given the relatively small number of elements that can be placed along the vertical axis.
The numbers from the Wikipedia article are likely false. Assuming 5000 T/R elements as stated above, the Type 346 would have a peak radiation power of 125kW per array. I suspect this may be too low. Perhaps that was the case for the first versions installed on the Type 052Cs. SPY-1D is somewhere in the range of 5-6 MW peak power, but it achieves this only by radiating through a single array at any given point in time.