I don't know what the staff's work schedule is but it won't take more than a couple days of wait before a complaint specialist reach out to you, have in mind there are many other open complaints, so it's normal if you have to wait a bit, but it won't be much.
Also, the complaint resolution can take weeks and it completely depends on how quick the casino reacts to it, once the complaint specialist ask you for more details they will set a timer for the casino to react to the complaint (it's a week long), if the casino doesn't communicate an extra week is given, if the casino fails to react then the case is closed as unsolved and the casino's rating is lowered.
This casino has no solved complaints (it seems they don't react to them), but you never know, it's worth a try
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