I am making the switch from altool to notarytool and I've run into a brick wall trying to submit our app zip. It is created using ditto -c -k --keepParent "path-to-app" "path-to-zip"
On submission I get:
Error: <app-name>.zip must be a zip archive (.zip), flat installer package (.pkg), or UDIF disk image (.dmg)
Absolutely baffled by this.