domain migration and mailboxes

domain migration and mailboxes

Hi,
We deceided to change our domainname to one which will be less time consuming if you have to spell it out with the nato alfabet. 
Will the users keep their mailbox or will it be replaced with a new one if we use this (see below) procedure I found on this forum

sign into Zoho Mail >> Go to Control Panel (Mail & Docs) >> Domains >> click the envelope icon across the domain name to remove Mail Hosting. Then delete the domain mydomain.com.
From Control Panel >> Domains, click Add Domain and add the new domain mydomain1.com and verify it by following this help page. You have to do this within 6 hours from deleting the first domain.
After verifying the domain, click Control Panel >> Mail Accounts >> click your account steve@mydomain.com >> add new alias >> add alias with the new domain ( steve@mydomain1.com). Refer to this help page. Then click the Change link across MailBox address and choose steve@mydomain1.com from the drop down and Save. Note that the email ID associated with the old domain will be cleared automatically after 6 hours from domain deletion.
Login to your domain management page for the new domain, delete any existing MX records and point the MX records to Zoho as given in this help page. It will take some time for the MX change to get updated after which you will start receiving mails here.
Note : If you want to receive emails for both the domains for some time, you have to move to paid plan and follow steps 2 to 4 alone. Refer to this help page to manage Subscription.