It'll be another 2 months (8 weeks) until the babies are old enough where any of the feed companies say they can have the layer pellets. Feeding them the pellets too soon, is too much calcium for them and can be harmful, especially their kidneys.
But the starter and the all flock are very...
Depending on how long it takes you go get to the store, I wouldn't give the chicks a layer formula, though a 9-week old might be better able to handle all that excess calcium than a younger chick.
I'd head to the store and get the all-flock (it has similar names), which is a roughly 18-20%...