Oh I am not saying that your birds are or are not 'pure', and being in the UK I have no idea at all. However here in the States it is estimated that nearly 70% of all IB's have some Spaulding in them.
Maybe, maybe not. A Dark Pied doesn't have to have any white on them at all. I have IB chicks from a pen with an IBBSWE cock over IBWE hens that throw White, Silver Pied, Pied, WE, and some of the IB chicks do not have any white showing on them but we know that both parents carry white so they...