Please don’t wait, the owner is appropriating property that doesn’t belong to them for their own use. They are also changing/damaging common property.
It sounds like the OC is useless so make an application for an urgent order to stop them and require them to restore the common property.
http://www.ncat.nsw.gov.au/Documents/ccd_form_strata_interim_orders_application.pdf
I think this is the second time I have suggested this in a week, I don’t think it is me, I can’t believe what people think they can get away with.