So you have a few options!! You can leave her till hatch then move her, you can screw or attach a small piece of strapping or material to the front of the box so none fall out, or you can move her completely now.
There are risks for each one! either you leave her and she is fine or you leave her and they may fall out and freeze to death or get killed. Putting the anti-fall ridge in front of the edge it will keep chicks in, but the ruckus of attachment or the change to environment may disturb your hen too much and she could abandon nest. You could move the entire nesting box if possible to a different location, the only problem here is if you can't move it. By moving the whole nest now you will either risk her abandoning the eggs or she will be fine and settle in to the new environment. It depends on the where abouts of your nesting box and the hen truthfully! I did make it sound worse than it probably will be! but I have had all of the above happen. You need to make the choice that is best for you and the chicks well being!
Ohhhh!!! If there are roosters who may in spite of a hormone flash either chase her off to mate or go in to try to it could result in broken eggs. If the community nest is often used by other hens that have access to the nest and are still laying and may jump in with her and lay other eggs it would result in staggered hatches and possible death to chicks in those after eggs that started incubation later. OR the other hens could kick her off and chicks could die due to getting too cold because they kicked her out for too long while they layed their egg. If any of these situations are possible I'd move her or the nesting box! if you don't move her I'd at least mark the eggs and when you usually collect I'd make sure she only has her marked eggs!
I had a girl who nested in front of my hay that sits on top of my pens for storage! it is 6ft high and this is her second time nesting there, despite me giving her heck last time, obviously she didn't listen! she was in a hole in between bails last time and was about 5 inches from the edge of the board. none fell off or ventured out but since she was in the bail the rats took one. she was back farther this time but none fell off again. I have had to move call ducks in from outside and move inconvenient nests once and a while but if she is safe in there I wouldn't move her. If my girls are safe I wait until she hatches either all of them or has an egg or even two left and then I move her whole nest. if possible I pick her and the whole thing up, if not the babies go in pockets or shirts the nest goes into a shovel, picked up with hands or in a pail and I put nest eggs and all into a pen with new bedding minus the transported nest which I either put in first then the bedding food and water or i make the bed and leave room for a nest. depending on your girl's personality is how id go by it! if I have a call duck who is going to flip I make the bed first so babies don't get trampled and she can be left undisturbed, if it's my silly pet bantam chicken who could care less where I put her as long as she gets to keep her babies and gets treats, food and water I put the nest in first and put the bedding around her so the bedding is level and easy for chicks to get around.
But like I said above I only move nests if they are in danger of being stepped on, extremely inconvenient, or if they are outside where predators can get at them. I leave them because chicks don't venture far for their first 12 hours to 24 hours! so most of the time chicks will pop their head out or stay under or right beside mom. especially if you don't put food or water close by to tempt chicks or mom off the nest! I always leave food and water if I can but if I need to move I wont put it anywhere close, I actually only keep water and grain in at the farthest place possible so the mother is not tempted to go show her chicks how to eat baby food! because let me tell you they sure know the difference and are a lot less likely to go for regular food!
Hope this helps!!!

Good luck!!! Hope all goes well!