How to add multiple postcode based fees rule
Once you want to add fees based on particular city or area then, you can add multiple postcode in each new line.
Example: There is Unites State's x city and area is y which contains few Postcodes like, 10001, 10002, 10003, 10008.
Screenshot 1: (Admin: Extra fees based on Country and Postcodes)
Screenshot 2: (Extra Fees front side view)