OK so the information I have been given is incorrect if you are right. However I do not see how that could ever be a secure system of testing - there is so much room for abuse
It would be just as unfair if those children taking the test at a later date were given a different paper, as no two papers can ever be of an identical standard of difficulty.
If they took a different paper, their results would not be comparable with those who sat the test on Thursday.
It might occur to a few parents to start ringing round asking which questions came up, but would you tell them? After all, it could mean that your child loses out on a school place because their child was better prepared!