Hello,
HikaShop use the address template system to display the formatted adresses.
That address template is a view so you can override it and also use some PHP into.
Depending the context, when loaded, the "address" is pass as a parameter of the view (the "displayAddress" function does. the "maxiFormat" function doesn't).
HikaShop mostly use the "displayAddress" function, the other one is used when we have to process a bunch of addresses (like a listing).
So you can add some PHP in your override (or via the HikaShop configuration setting which will put your content is both front and back templates) and get the address object which is available in the params of the view.
Regards,
Jerome - Obsidev.com
HikaMarket & HikaSerial developer / HikaShop core dev team.
Also helping the HikaShop support team when having some time or couldn't sleep.
By the way, do not send me private message, use the "contact us" form instead.