Do you have a source for that? I've never found confirmation other than seeing a picture of a four round launcher in their bomb bay mounted on a rotary launcher. I certainly never heard of a total bomb load of 192. That would be rather significant change to the B-2's combat capability compared to the 80 JDAM configuration.
The Air Force still lists B-2 as a future integration target for SDB. No indication that either SDB-I or II has been integrated so far.
The USAF and NGC integrated SDB after I left in 1996. The B-2 uses the Smart Bomb Rack system (2 per bay) which can handle a variety of free-fall and GPS guided bombs for 2000, 1000, 500, and 250 lb (SDB) units, plus other munitions as well, very versatile rack system. The big boy GPS munitions like the 5000 lb and 30 klb units and of course the missiles use the RLAs.
The Smart Bomb Rack yes, but I've never seen any indication it's for anything other than 500-lb JDAMs.
There is probably no way, physically, to put multiple SDBs in a rack designed around 500-lb weapons. Certainly not 192 of them.
The BRU-61 rack is reportedly (per multiple sources) mandatory for SDB-I at least (yes, we've seen Laser SDB in single fits on UAVs but nothing else, AFAICT). The form factor for the BRU-61 with 4 SDB is much more like a 2000-lb weapon -- 143 inches long (vs 149-152 for a GBU-31) and 1,460 lbs (vs 2,036-2,113 for the GBU-31). So four SDB on their rack replace one 2000-lb JDAM, which gives you a max of 96 in a B-1B or 64 on a B-2. Which is a step backwards from the SBR with 80x500-lb JDAMs.