Hi Sarah, thanks for getting in touch.
You can get a list of customers and leads for a given delivery area, by going to Settings → Delivery settings → Delivery areas and clicking the View customers in area button for the delivery area in question. This will include both customers & leads, and from that page, you can further filter this list with BrewwQL.
In addition, we have Customer and lead mapping and visit (field sales) route optimisation as feature request. It is alreadyhigh on our list and should make planning visits even better, but if you’d like this too, please can you vote for it with the button in the top-left of that page as this will help push it even further up the priority list.
I hope this helps, but please do let us know if there is something else here that we can help with.