Where does all this misinformation come from??
There is NO P1 requirement for starting the CPL flying course.
ICAO PPL with no extra hours to start the groundschool
PPL with total time 150 hours to start the flying course
Flying course complete, all written examinations passed, night qualification passed, radio telephony exams passed, class 1 medical passed (doesn't need to be current at class 1 standard) to take the flight test
PPL, CPL skill test passed, 200 hours total with 100 hours P1 for licence application.
In fairness to Northen Highflyer, you may need 70 hrs P1 if you do the complex part of the CPL course in a multi engine aircraft - but not if you do it in a single engine (but that woulod depend on which school you train at).
As said above, 5 hour credit towards I/R if you have CPL - as not said above, 10 hour credit to CPL if you have I/R.