That is a good plan...and please don't forget to post pictures as the chick grows up.
We always say that the E-Locus on a CL should be wildtype - e+ - Because wildtype plus barring is what gives the autosexing -- and Punnett's original notes show how he did it.
That being said - we have no idea what the E-Locus genes of the "Chillean Hen" were -- and the BPR -- used to get barring genetics -- part of the autosexing, isn't a wildtype.
Now, add to that the fact that some folks who wanted to improve the breed -- didn't know what an E-Locus was -- but knew that they had a chicken that laid more frequent - or larger eggs, or had lighter colored plumage -- so they thought maybe that would be a good out-cross -- and the CL is a real Heinz-57. Although I may be the only one with the theory, IMO - the "ambiguous autosexing" is traceable to some unexpected genes on the E-Locus.
I expected something a little more like the wild type down pattern when I crossed the Pita with the EE's nothing in the pairing would make me think they could be sexable at hatch either. I was just surprised with chicks that had such black down. CLB are what I call a patchwork chicken.So many things going on with this breed Im amazed that they even developed a standard. I love them though. It will be interesting to see how the chicks look from the CLBxEE. Ill have to separate at hatch to be certain I can sex the CLB girls.