Thanks Jason, but either this doesn't work or I'm missing something.
I understand the since_id (though this seems to use not the order_number but the "id").
The thing I NEED is I want only orders where the customer object has been tagged, like "RETAILER."
The application here is a orders for retailers where such orders are fulfilled from a warehouse rather than individuals, where the orders are small and handled within the office.
I know I can get all the orders and filter on the client-side, just hoping there is an easier way to make the returned data smaller and only what I need.
Query parameter does not work with the Order API so you will have to bring a big chunk of orders and filter them on your server side then decide what to do with that. That been said I suggest you use created_at_max and created_at_min to delimit the number of orders you bring, to be sure how many pages you must pull I suggest using the /orders/count.json?created_at_max=&created_at_min to see how many orders you need to pull. divide it by 250 (which is the max amount you can get per page.) and just loop the get orders.json api to pull only the info you need. and filter on your side. Its a hassle but for now its the only way I think. I wish you the best of lucks :D