In this case, Charge Processing pulls everything with Pull Cycle = 20 or null if the Charge Processing job has the Pull Cycle parameter set to 20.  When Charge Processing pulls a Transaction with a null Pull Cycle in a job that has a specified Pull cycle, it marks the original PL with that Pull cycle prefixed by an N (so N5 = when it was pulled in the Pull Cycle 5 run).  This is normal Charge Processing behavior.