Hi,
I think that this is done by the code:
}else if(params.type=='shipping' && (!selected || d.getElementById('hikashop_shipping_methods') || d.getElementById('hikashop_payment_methods') || d.getElementById('hikashop_checkout_cart') )){
d.forms['hikashop_checkout_form'].submit();
}else if(params.type=='billing' && (!d.getElementById('hikashop_checkout_shipping_address') || (d.getElementById('same_address') && d.getElementById('same_address').checked) || !selected) && (d.getElementById('hikashop_shipping_methods') || d.getElementById('hikashop_payment_methods') || d.getElementById('hikashop_checkout_cart') )){
window.location.reload();
in the file "address_select" that you can edit via the menu Display>views.
Try removing it and see if that does what you want.