Change from Semtech UDP to Basic Station

I originally created a gateway as Semtech UDP now I want to change it to Basic Station which wants authentication. I deleted my gateway but when I try to create a new one with the same EUI TTN tells me that it already exists.

Bet you £/$/€1 it doesn’t.

This is the second outing for this issue this week, re-read the error message, perhaps use the actual error message to search the forum for the weekly ask of this question and don’t delete gateways, just edit them!