"Claims" mean that's the number they haven't been paid on this one therefore that the size of the dispute. there would have been previous invoices paid to date but that's the headline number. unfortunately you would have a better chance punching on with Rio or BHP, Roy Hill are tough and if they don't think you are owed it then your not getting it. they would be defending several this size at any one time. its a Hail Mary move where you name and shame to see if RH might want to throw some $$ at you to shut you up. the supply chain will be shutting down now and the banks starting to play games I suspect. sorry to the holders and everyone involved, not good for the whole industry.
