SM4 Pirate, thanks for the support. I think the $500,000 per annum is correct, as it is basically the cost of the satellite links and the power etc for the transmitters. Remember that the HF Flightwatch remains open, and I understand this means the same staffing levels – maybe someone else can elaborate.
By the way, there is money in the DTI (Directed Traffic Information). Everyone pays a full IFR enroute charge for DTI – the same as if you are flying in controlled airspace. It certainly is an earner for Airservices.