Iberia´s 747-200s only have 8 P class seats at the upper deck. There´s even one of them that only has 4 seats.
As you said before, 743s have 12 P class seats up there.
Anyway, this is all going to change this year. First class is going to be removed from all Iberia´s flights. Business Class is going to ve revamped and new seats will be introduced, with a very nice design and totally flat when fully reclined. Iberia´s long haul fleet will offer only two classes of service...I already have some brochures i took yesterday at Fitur that show some pics of the new seats.
Sadly, at the moment there are no news about changes to IB
´s economy class seats.