Any suggestions on how to prevent them from laying there?
A few different things could be going on. When they first start to lay many pullets have total control. The egg is formed perfectly (though usually small), they know where to lay, and they know where to lay. But occasionally it takes one a while to work the kinks out of its system. If they haven't figured out when to lay they may drop an egg overnight from the roosts. Most can usually tell when an egg is coming and go to a nest. But some don't seem to catch on immediately so they drop the egg wherever they may be, just walking around or perching on the roosts during the day. If either of these are what's going on they should get some control pretty soon. I don't know of anything to fix either of these other than patience. How many are doing that and when are they laying the eggs?
Some have total control. It's possible they have decided that that area is a safe place to make a nest. If the eggs are laid during the day and they are always in the same spot, that is their nest as far as they are concerned. That will take work. I made some of my nests so I could lock a hen in there if I wanted to. That's come in handy for different things.
The way I handle a pullet or hen laying where I don't want her to is to lock her in a nest until she lays when I catch her on that wrong nest. You may be able to just pick her up off of that nest but I usually have to use a fish net. Typically they lay the egg within 30 minutes of locking her in the nest but I had one take 3 hours. Usually I only have to do that once for her to get the message but that 3-hour hen took two consecutive days. She was not my favorite for different reasons. I'm retired so I can go down there several times a day to catch the laying. Mayne this weekend for you?
Is your roosting area set up where you can block it off for the day? If you can lock them out of that area that would force them to lay somewhere else. You might have to be down there pretty early to block it before they lay.
Also, is it unusual for them to be 6 months old and still not lay eggs?
No, not unusual. I've had pullets lay their first egg at 16 weeks, I've had some wait for nine months. I've had them lay their first egg the first week of December, about the shortest days of the year, and lay regularly the rest of the winter. I've had hens finish the molt and start laying in the middle of winter. I do not use extra lights to lengthen the days.
You've had a few that recently started. What does that tell you about how long the days have to be or when they can start? I've seen a lot of posts on here that EE's are among the last to start to lay. Which ones of yours were among the first? Be careful believing conventional wisdom. Basically they lay when they lay. That's frustrating and aggravating. I understand that, I had to wait nine months for some of mine once. It is quite possible more of yours will start laying pretty soon. It is also possible some will wait for the longer warmer days of spring.
Good luck!
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