Hmm, if they are a week apart you can candle them and mark each batch. It should be pretty apparent which group is which. After that, I would separate the hens. That way one is on each group.
I had 3 silkies sitting on eggs that ended up being almost a week apart, I was too loosey goosey and hadn't tracked as well as I should have. It did end up biting me on the rear and I had to incubate 3 of the 4 eggs when they were abandoned by all 3 hens to care for one little chick.
I had 3 silkies sitting on eggs that ended up being almost a week apart, I was too loosey goosey and hadn't tracked as well as I should have. It did end up biting me on the rear and I had to incubate 3 of the 4 eggs when they were abandoned by all 3 hens to care for one little chick.

