Concept for cut down costs and increase revenue

Question=
I am new here and this is my first thread. So I hope some kind soul out there will answer my query.

I am working as a Call Centre Manager in a MNC. Currently, my company has call centre around Asia Pacific. Each and every individual country has a call centre respectively.

However, during a recent management meeting, the top management has requested us to look at centralizing the call centre in Singapore. This would mean we will eradicate all call centres in each and every country and set up a regional call centre as a HUB in ONE country. The top management think by doing so, we will be able to cut down costs and increase revenue.

My questions are how can this be cost effective? Having oversea customers calling in is definitely more costly right? If I am a customer calling from Australia, wouldn’t it be cheaper if the call centre is in Australia? Setting up a regional call centre in Singapore would mean a Australia customer will now have to make a long distance call to Singapore and the hotline is toll free meaning we have to pay for all telco charges.

Can someone advise me why it is more cost effective to have a centralized regional call centre? I don't understand.

Answer=
Centralize call center has different concept. In all the regions, you company will establish one hub where only communication devices will be kept.

All the hubs will be connected with the centralize call center through leased circuits (size of the circuit will be decided based on the call volume, normally one channel require the circuit of 8 KB). So let's say if a customer has to call from India to your call center in Singapore, he will dial the local number, which will land in the hub set up in any big city in India. Then the call will be sent through VOIP having the leased circuit as medium to your call center and it will be handled by the agents.

It's cost effective solution, because you don't have to invest in the property, management cost and all other costs