Shipping Method Post Code Restriction Bug

-- HikaShop version -- : HikaShop Business: 2.6.1
-- Joomla version -- : 3.4.8
-- PHP version -- : 5.5.31
-- Browser(s) name and version -- : Firefox 45
-- Error-message(debug-mod must be tuned on) -- : "No shipping method found for your location"

We've discovered that there may be an issue with the post code restrictions for shipping methods, and we believe this is a new issue that has presented itself in a recent Hikashop version.

U.S. zipcodes are most often used in a 5 digit format, however, the post office will use a 9 digit zip code for more accuracy in locations.

"The basic format consists of five decimal numerical digits. An extended ZIP+4 code, introduced in 1983, includes the five digits of the ZIP code, a hyphen, and four additional digits that determine a more specific location within a given ZIP code."

We have a shipping method, using the manual shipping plugin, restricted to post codes within the range of 20154 to 99999. If the customer's post code is entered as 20171, for example, the shipping method works correctly. However, if the customer uses the 9 digit post code like 20171-2986, the shipping method restriction excludes the post code as a valid value for the shipping method.

This may be a bug, or perhaps the max and min post code fields work differently in the latest version of Hikashop? The reason we believe that the function has changed is because we had a returning customer use their previously-saved address with the 9 digit zipcode and the shipping method error appeared.

Ok, however, technically 20171-2986 should not be understood as 201712986, but rather 20171-'subset'.

The +4 code is a 'subset' of the 5 digit zipcode, because it breaks down the area into smaller sub-areas. So, 20171-'anything' should be viewed as less than 20172.

If 20171-2986 is understood as 201712986 then that would mean two shipping methods would need to be created for each range, the 5 digit and the 5 + 4 digit, to be prepared for either customer entry.

As a quick fix, I've limited the address post code field to a max of 5 characters ... nip it in the bud!