I check the nest boxes when I let my ladies out at 6:15 a.m.. I have three who consistently leave me eggs by then. I don't check again till about 3:00 p.m. There are usually five there then. On Sunday I let them out into the yard to range at around 7 and only got four eggs that day. I think the others layed theirs in the yard somewhere.
We collect eggs daily, or our EE will break and eat them. We also check around in the corners and under the broody's, so we don't accidentally let anybody hatch new chicks. They hide their eggs under litter and feathers until they have enough, then they move their clutch under a broody. They're clever that way.
Actually, each chicken can vary in their egg-laying routine, so once you get used to the peculiarities of your flock, you'll know how often and when to go.
I personally check twice a day if my DH isn't at home during the day (his reward for being between jobs currently is chicken-sitting
).
I normally check at 8am (most of my girls lay by then), and then if I don't get the same number of eggs as chickens, I'll check when I get home in the evening too.
My birds do not currently follow the 25 to 28 hour cycle, and don't seem to have their dayplanners straight