The nib has a very distinctive design on it. Being a pen collector myself, I know that the Sonnet is pretty much the only pen with that design. No 3rd party nib manufacturers use that design ( Bock, JoWo, generic IPG Kit Pens, etc.) on their nibs.
Also they have a delivery date of March, with the project ending in late February. No way can someone manufacture and delivery a new fountain pen within a month.