I remember reaching the same juncture as you and having to question the theory. My stones also kept coming.
The type of stones change as you progress and the most important stones may still be waiting. I would suggest that you keep going and take stock around 20 flushes. You should also bear in mind that if your biliary system isn't functioning fully them the bile will quickly make stones even between flushes. You should see them getting softer and lighter. Also is the bile is too thick it will precipitate in the ileum forming balls of bile, known as primary enteroliths.
You could consider flushing at 4 weekly intervals after the initial enthusiastic start. This gives plenty of time for the biliary system to settle down.