This first photo was taken from Mt Roskill at 11am approximately. The second photo shows the same trail about 15 minutes later. This was evidently not a vapour trail, as it lingered and spread out.
Thank-you very much to Tavia Kane of Sandringham, Auckland for sharing this video of the same trail, which she took at about 11am this morning from Sandringham. Unfortunately, the plane involved was not identified using Flightradar24.com.
Showing the same aerosol trail. This photo was also shot in Auckland and by Helen Wd of the Facebook group, Chemtrails over NZ, which currently has 1484 members. Note the aircraft in the foreground of this photo revealing the monstrous size of the aerosol trail.