Australia's tour of South Africa has been postponed indefinitely. It is extremely unlikely that the series can be rescheduled in time for the results to count towards the final of the World Test Championship, set to be played in June at Lord's. And that means a few fresh tweaks to the scenarios in the run-up to that final.

Does this mean New Zealand are through?

Yes. Australia, marginally behind New Zealand on the points table at this stage, will not get the opportunity to go past them now. India and England are both in contention, but since they play each other, only one of them can exceed New Zealand's points percentage of 70. That means New Zealand versus…

Australia, possibly?

Australia are not out of it yet, but they will be ruing the four points they dropped because of a slow over-rate against India in the Boxing Day Test. Had that not happened, Australia would have been level with New Zealand on 70, which would then have brought the runs-per-wicket ratio into play (that is the ratio of the runs scored per wicket lost, and the runs conceded per wicket taken). Australia's ratio is currently 1.39 while New Zealand's is 1.28.

This means Australia would have stayed ahead of New Zealand if they hadn't been docked those four points, and would have been certain of qualification. Now, they will need India and England to help them out: if the two teams share the total points on offer from the series in such a way that their overall percentages drop below Australia's 69.17, then Australia can still make it to the final. That can happen only if the series is drawn (by any margin), or if England win 1-0, 2-0 or 2-1, or if India win 1-0.

What do India need to do to qualify?

Both India and England will target Australia's points percentage - whichever teams tops 69.17 will qualify.

India need 70 points from the four-Test series to go past Australia. That means they need to win by at least a 2-1 margin - that will fetch them 30 points for each of the two wins, and 10 points for one draw; 3-0 or 3-1 or 4-0, of course, work even better.

And England, don't they have a shot too?

England need 87 points from these four Tests to go past Australia. That means they need to win at least three matches. History is against them there, though - the last time a touring team won three Tests in a series in India was West Indies, in 1983-84.