1800 km > Israeli experts are rumored to have estimated from the disclosed weight and dimensions of Tayfun-4, this was on TV news
561 km was demonstrated by Roketsan and video was shared about it. Rounding this number to 600+ is a safe estimate anyone can make for Tayfun-1
This information was out there within a few days of the missiles' first appearance. I am surprised that there is even single person on defencehub who hasn't heard this.