it's been a while, and now i think what i saw back then was a plane with a short contrail - illuminated by the sunset.
i've been told that planes can have short contrails. And i think the contrail of this plane was possibly illuminated by the sunset to it's firey red orange colour that made it look like flame.

Still, it was spectacular, and i'm glad at least 3 other groups thought it was spectacularly interesting enough to seek out this thread on the internet to talk about it

I put all of the data into google earth and it's cool how it all matches up. It seems to be something traveling in the general direction of south east towards Ipswich, it became occluded by cloud possibly somewhere between Lowood and Mount Cootha.