I have a question please: I have 4 girls who are about 16 weeks old. Two are white leghorns and two are barred cochin bantams. Last night I used the last of my grower feed and I would hate to buy another huge bag when I am pretty close to needing layer feed. Two of the hens are already developing their 'red' waddles and showing signs of laying...but I don't want to start them on the layer feed too soon. Is it very important to wait until they start laying or can I buy the layer feed this afternoon? Thanks for listening!