From the site:
The first certification is exclusively for the CUH-1100 A, while the second is for both the CUH-1100A and the DUH-T1100JA, which indicates the non-retail testing kit of the console.
The difference between the two new certifications and the original (and also between the two new certification themselves) is in the antenna power and frequency pattern, most possibly meaning that there will be two slightly different models under the same code.
Again, this doesnt mean that there wont be more differences, but this kind of certification is exclusively dedicated to wireless equipment, so it wont mention other parts.
What we do know is that the new model wont be a full redesign, as according to Sonys coding standards that involves an incremental change in the first digit of the number, while strictly internal evolution is indicated by the second digit like in this case. Its also not a bigger hard disk, as that comes with a change in the final letter of the code (IE: A would be changed to B).
With Gamescom and Tokyo Game Show incoming, we might get to hear something official about this soon enough.