Is there an Exchange best practices for changing a company domain name?

[Anonymous]

We've been doing tech support for a medical suppy company for several years.  They have decided to rebrand themselves and have obtained a new domain name.  They have around 39 user licenses. (There are 7 PCs in the office plus outside sales people and physical therapists.)

Here's the breakdown of their account

25 Exchange Online (Plan 1)
6 Office 365 Business + Exchange Online (Plan 1)
3 Office 365 Business + Office 365 Enterprise E1
1 Office 365 Business + Office 365 Enterprise E1 + Exchange Online
5 Office 365 Business+ Office 365 Enterprise E1 + Exchange Online (Plan 1)
5 Office 365 Enterprise E1

What is the correct way to move them into this new domain?  For one thing, many licenses are paid up for the year.  Also, is there anyway to provide continuity from the old email addresses to the new?  Or must we just export all their present accounts to PST files and simply attach them to the new Outlook profiles as archived data files?

Any advice would be appreciated!

PS - If I'm in the wrong forum, I'd appreciate a pointer to the right one.

[Anonymous]

Hi @Anonymous, thank you for asking. Is this for CSP? @Anonymous, please can you help with the above question?

[Anonymous · Accepted solution]

Hello @Anonymous,

For this topic I found below reference articles: 

https://technet.microsoft.com/en-us/library/cc781575(WS.10).aspx

https://technet.microsoft.com/en-us/library/cc738208(v=ws.10).aspx.

Hope this is useful.

Best regards,

Roxana