In todays news
http://www.stuff.co.nz/business/money/9819249/Telecom-charge-for-old-school-bills

I hope they will be first contacting people and warning them about the change, before billing them, so they can then choose to elect to receive paper billing or not prior to this change going through. Otherwise they are going to get a lot of annoyed people. 

Doesn't look like they are passing the cost savings onto the customer though