Actually we do know the answer, it's clearly stated and you also provided commentary on it. Don't worry OzJ, because I feel an obligation to respond to vaga, you will also get the benefit of an educated response.
KAB was having troubles with it's solvency. Given KAB was assuming the role of depository for ISX's Netherlands based operations it's ability to process transactions, (send and receive money) was compromised during this period.
ISX have indicated that KAB informed them this would be a temporary situation. They were experiencing some sort of short term difficulty that would then be resolved. On that basis, ISX did not think there would be a material effect on their operations in this region over a meaningful period. Much like a bank experiencing an ATM or EFTPOS outage. This affected performance over that period (July, Aug and Sep) though it was not a significant impact.
After Sep 18 the dutch regulator stated they would take control of the bank and ISX could conduct business as usual. Once the regulator had a proper handle on the situation more information was provided, and the KAB saga becomes history.
As KAB was providing deposit service for ISX, they had to go out and find a new bank, set up new operations and infrastructure to service clients. This obviously then had a significant impact on ISX's operations and performance through the last quarter of 2018.
ISX Price at posting:
$1.07 Sentiment: Buy Disclosure: Held