I have a customer who's moving away to another hosting provider; he has been slowly moving his accounts, and now for some accounts, he has them hosted elsewhere, with the DNS at the registrar already changed and pointing to the new server, but with the hosting account still existing here in my server, even though the domain points elsewhere.
I noticed our last few emails to the customer, to a domain already hosted at their new provider, are residing in our server, at home/user/mail ..
Since the account the email is going to is still in our server, does exim wrongfully only store the email locally rather than sending it to their new server?
What would be the best solution to this (without removing the account), delete the DNS zone through cpanel? change the ns records to their new server?
Or can exim be configured to check for the destination server IPs to send to even if the account already exists locally?