Dial Zulu Soft Phone Directly

Is it possible to dial the Zulu Soft Phone of a user directly without ringing his linked extension, so that only Zulu rings, but not the phone?
Can I change the Zulu prefix 90 to something else?

No Zulu does not have ita own extension. It’s just another device for your main extension under the covers and devices in asterisk can not be dialed direct only extensions.