SF Pastel Blue males that are WB or LB (so, a WB or LB visually Silver that is "SF Yellow") will have dark beaks while in the nest.
They look almost identical to pastels as hatchlings (minor differences in the nodules and mouth markings though) but where you see the difference is when the pins start coming in white instead of pale grey.
It's the same for PB Dilutes vs WB or LB SF Yellows; DF Yellows and Yellow hens will always have pink beaks, SFs will always be dark
And again, PB Dilutes and WB/LB SF Yellows look very similar as hatchlings, but the difference is the pin feather stage.
