Depends on the holster, in my limited experience.
My concealed carry holster (a leather/kydex inside the waistband holster) works with my old DUTY P07 or my P09. The P09 barrel/slide does stick out the bottom of the holster though and digs into my hip if I try to sit down wearing it, so I don't carry the P09 in it after that one attempt.
I bought a drop leg holster from CZ USA for the older DUTY P07's. The P09 and the newer model P07's would not lock into that holster until we removed the locking mechanism and scraped some material off it allow it to pivot into the locked position. Evidently, the trigger guard on the new P07/P09 is slightly thicker, or has a little bit different orientation, or something, that keeps that particular holster from working with the newer trigger guards.
