From what I have gathered --since they have not yet laid out all the details of this new light-- is that the 144k are now the domestics along with the earthlings when it comes to the channelled AUTHORITY. The rewards stay the same and are grandfathered in at this time.
The Faithful and Discreet Slave only exists when a special gathering takes place. When these special 8 domestics gather, they combine and transform into the Faithful and Discreet Slave, kinda like a theological VOLTRON.