Pelfrey will be going back down, but this still leaves 5 pitchers... Martinez, Glavine, Hernandez, Trachsel and Maine. Plus Bannister which makes 6.
What will probably happen is that they may go 6 man again to see how Bannister pitaches a few games. If he doesn't do well... they'll send him back to the minors and the rotation will stay Martinez, Glavine, Hernandez, Trachsel and Maine.
If he does well, he'll be left in a rotation spot and either Hernandez or Maine (whoever is doing worse) gets moved into the pen for a long relief type role. Thus making the final rotation... Martinez, Glavine, Trachsel, Bannister, Hernandez/Maine with a high possibility of Maine being the starter and El Duque the reliever.