I take it to mean they're spending money on the investigation...

I take it to mean they're spending money on the investigation phase and maybe there will be a further provision required for remediation. For it to still be under investigation some 3 months or more after becoming aware of the problem tells me it's a pretty complicated issue.
I'm not sure if it's an issue that will be soon solved and we never hear of it again or it's evidence their systems aren't up to scratch which will require more $$ to be spent.
The inflows were brilliant, hopefully they aren't impacted in the future from any negative publicity. Funds management is 100% reputation