old_contents: # Copyright (C) 2021 Open Source Integrators
  # License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
  
  from odoo import models
  
  
  class ResPartner(models.Model):
      _inherit = "res.partner"
  
      def _prepare_invoicexpress_vals(self):
          self.ensure_one()
          vals = {
              "name": self.name,
              "code": self.vat or "ODOO-{}".format(self.id),
              "email": self.email,
              "address": ", ".join(filter(None, [self.street, self.street2])),
              "city": self.city,
              "postal_code": self.zip,
              "country": self.country_id.invoicexpress_name,
              "language": self.lang[:2],
              "fiscal_id": self.vat,
              "website": self.website,
              "phone": self.phone,
          }
          return {k: v for k, v in vals.items() if v}
  
new_contents: # Copyright (C) 2021 Open Source Integrators
  # License AGPL-3.0 or later (https://www.gnu.org/licenses/agpl).
  
  from odoo import models
  
  
  class ResPartner(models.Model):
      _inherit = "res.partner"
  
      def _prepare_invoicexpress_vals(self):
          self.ensure_one()
          vals = {
              "name": self.name,
              "email": self.email,
              "address": ", ".join(filter(None, [self.street, self.street2])),
              "city": self.city,
              "postal_code": self.zip,
              "country": self.country_id.invoicexpress_name,
              "language": self.lang[:2],
              "fiscal_id": self.vat,
              "website": self.website,
              "phone": self.phone,
          }
          return {k: v for k, v in vals.items() if v}
  
subject: use latest Odoo address, instead of (old) stored ones