I forgot to add something. If you submit a "correction" you can go back and delete it simply by utilizing a "trash barrel" icon. If you know who incorrectly changed some of your relatives you can always ask them to remove the correction/addition. I believe when Acom first introduced the "correction" feature you couldn't delete it later but that has long been remedied so there shouldn't be too many that can't be removed. Only the original poster can delete their own message.
Best of luck with your research.