If it's per unique pair of telescopes then will the data rate scale O(n^2) to the number of dishes? If that is the case then holy balls the final SKA will produce a lot of data.
It's pretty crazy! And yes, the number of measurements scales as N(N-1)/2, so O(N^2). The funny part about this was, the SKA has been in design for >15 or so years at this point, and they had to predict that computational hardware would be good enough to make it work when they actually start building it! The hardware in 2000 wouldn't have been anywhere close to capable of powering the SKA's correlator. This is actually also a game that they had to play with the Large Synoptic Survey Telescope (LSST)[1], breaking ground now, with the relatively pedestrian 20 TB a night for archiving.
[1] https://lsst.org