How to gain access to Order Routing Location Rule function template?

I am building an app and want to implement an order routing location rule function.

I have tried running shopify app generate extension but the function is not listed.

Also tried, shopify app generate extension --template order_routing_location_rule but got an ‘Unknown extension type: order_routing_location_rule.’ error in my terminal. I’ve set up a shopify plus dev account as well to test my app.

Can anyone point me to the right direction? Thanks

Thanks Luke for the swift reply. I’ve seen that notice as well but need clarification. I already am a shopify partner. Do I need to also have an actual shopify plus store as well before I request it? I am not a merchant, just a partner who wants to cater to shopify plus stores with my app.