How to migrate Zoho hosted email and CRM

How to migrate Zoho hosted email and CRM

We use Zoho hosted business email (and Zoho CRM services) with www.olddomain.com and now want to migrate over to www.newdomain.com also hosted by Zoho.

We added, validated and set the primary domain www.newdomain.com
We created MX records and activated the mail service for www.newdomain.com
We set the default mail account to name@newdomain.com

 
The problem...

Existing mail accounts still appear as <name@olddomain.com>. The CRM mail add-on still sends email from <name@olddomain.com>. There is no option in CRM to change the sent address to name@newdomain.com.

Is there a way to fully migrate from one Zoho hosted domain to another?