Of course NBRI's toxic lenders are "accumulating". They have to "accumulate" because if they were to dump as fast as they really wanted to, NBRI would already be at TRIP_ZERO_ONE and NO_BID.
The toxic lenders know they're holding worthless paper, but they're still smart enough to feed it into the market a little at a time so they don't cause a total NBRIselling PANIC!