Boulton Paul Defiant

Hey fellow forum members, I need some help on doing research on the Defiant. I am building a model of a nightfighter version flown by a free Polish crew. It states on the instructions that an addition to the rear defensive turret, that it had installed two forward firing guns. I thought that all Defiants had only the rear turret as offensive weapons. Can anybody shed some light on this subject? Do ya’ll have any wartime pics? 😎