X26 days is perfectly fine. Yes, you should collect them (store them in an egg carton around 50-60 degreesF and turn then daily) and when you have what you want set them all together. Most people set eggs that are a week old or less. Most articles recommend 10 days and under with the consensus being over two weeks the hatch rate declines significantly. The Brinseas are highly recommended and one of the most fool proof incubators, so you are off to a good start. Good luck on your hatch!