Known proven inheritance in Pyrrhura's:-
CINNAMON = SEX-LINKED RECESSIVE (plum eyes)
YELLOWSIDED = SEX LINKED RECESSIVE(normal eyes)
BLUE(pastel blue) = RECESSIVE (normal eyes)
All mutations can be combined to create new colours eventually such as Steve Garvin's birds at the The Feather Tree website with his Green cheeks, " pineapple" are a combination of yellow sided x Cinnamons.
(Below: Pineapple's = Yellow sided x cinnamons combination)