If we move after March nearer to Wimbledon is there any chance getting place.
From the phrase "nearer to" I assumed that curiousappa's family did not still have a house in Wimbledon and were instead considering a move back to the area.
If that is the case, they would not have an in-catchment address to use for the October 31st deadline regardless of the finer details of defining which house would count as temporary and which as permanent.
If you intend to move back before the new school year, then sit the test, and apply for change of address. You will be eligible to be added to the list after 1st March and if your score is above the qualifying will go in at top of list.
Yes this would be possible however it does involve risk. If curiousappa's daughter scores highly enough to be added to the list but not the top of the list, she may not receive an offer at Tiffins at all. There are always people who make the waiting list but never actually receive an offer.
That then leaves the family as late applicants in Wimbledon at a time when all other school places will have been allocated because anyone moving to new area after the deadline are treated as late applicants which means their preferences aren't considered until all other on-time applicants are processed.
Therefore even moving very close to a good back up school in Wimbledon early in winter or spring would not guarantee a place at a preferred school should the Tiffin waiting list not work out.