Just to clarify.

When you say upgrade the exchange I think you mean upgrade the broadband equipment.  We are talking about two separate pieces of equipment.

The exchange is the switch that connects your landline phone calls.

The broadband equipment connects you to the www, piggybacking onto the copper pair that delivers your landline.

The broadband equipment just happens to be co-located in the same building giving easy access to the copper network and in some cases the fibre network.