How can I enabled USPS Shipping method for APO Addresses Only? I have USPS working fine, however we only want to use it for US military addresses (APO, FPO or DPO) only. Our primary shipping method is UPS which is working fine, however our customers are now selecting USPS address and we are loosing money on those shipping methods.
How can I lock down USPS shipping method to only be an option for APO addresses? Currently in Magento backend there is only options to select Applicable Countries.