Sorry but that worries me. Your birds are no more than 14 months old. If the eggs are fertile, they may need some help to care for them. If you can´t step in and help in the moment, chicks will die. You won´t have time to research on the spot. You will panic and something could go wrong. (Your birds were 4 months old when you got them so I don´t think you know how to handfeed.) If you don´t research and find knowledge now, you won´t be able to help your birds - not a good ending. I´m not saying you must destroy the eggs. But if you are going to leave them then you must prepare for many possible outcomes, buy all the equiptment they will need and find them a loving home -with you, or someone else. You must start thinking up a plan now because if you realise you can´t get away from work or you have other commitments, now is the time to remove that last egg. Are you home a lot? (don´t work, work from home or work/go to school but can get home frequently on breaks) A chick needs feeding between 2-4 hours depending on its age. Can you do that? or is someone else avail. to do that? Did you watch the video in my first comment? I find it´s easier to see inside the egg if it´s not daylight. So closing curtains will help you. Open the little picture in my first comment. If you see lines in the egg, they are veins and it is a fertile egg. It usually glows quite orange almost red. If you don´t see anything, it is infertile or too soon. If you look at the egg 7, the one laid this morning, you will see it is yellow. you can´t see anything inside it. ok? if the other eggs look like this one, remove them, they are not fertile and have expired. Egg 7 looks like a non viable egg right now, because it is fresh, so you can use it to compare. Leave egg 7 in the nest box if you wish to proceed with this clutch. If you decide to destroy the egg, the best time is now while nothing is growing inside it.