O2's billing emails, and a well known bank have broken DKIM signatures as they are improperly forwarded. No chance of getting through to their tech support, es

O2's billing emails, and a well known bank have broken DKIM signatures as they are improperly forwarded. No chance of getting through to their tech support, especially since these types of email are usually from a no-reply@ address and the people manning the phones are not the mail server admins anyway.