Firstly, bad luck! It happens, you can get a flock has never had prolapses, then has several prolapses one year, then never again.
If when the lambs come they don't seem to be overlarge and the ewes not fat, then all you could say another year is you would limit the amount of good grass they have in front of them when they are in the later stages. Two small feeds of cake a day - not necessarily a high-protein cake - and less grass might keep their insides less overfull, but nutrition at the right level.
They can lamb through a spoon no problem, so don't worry if you do miss it she will simply evert the spoon and then the lamb(s) will come. You can snip the spoon off whenever.
With the ones with stitches, you really do need to cut them once the lamb approaches, or she can do herself and or it some real harm.
A tip for shrinking a prolapse is to wash it then cover it with granulated sugar and wait. It really does shrink before your eyes. Perhaps 10-15 minutes or so to reduce from nearly football size to two grapefruits, which I can usually get back in and spooned.
Mostly they don't prolapse again when they lamb, but you can get ones who don't stop pushing and it all comes out - lambs then uterus, and you can get ones who partially prolapse before the lamb is engaged into the cervix and then can't lamb at all. Both cases are vet urgently.
But in my experience, of I guess maybe 20-30 prolapses over 14 years, (of which all but a very few were sorted with a spoon), it's almost always fine.