So, NAB duplicated a number of EFTPOS transactions? I noticed the notification on NAB's log-in screen on 13 February, and it stated that the solution was [still] "underway" with reversals to occur on that day or the next. The notification had been removed by the next day.
Errr, the transactions were on 7 and 8 February......up to 6 days beforehand. I'm uncertain when NAB just happened to detect the problem (but the tone of the notification suggests that it may have taken a few days). I don't know how many of these transactions there were, but even if there weren't many, it doesn't inspire confidence when it takes a week or so to identify and sort out an issue such as this.