Hi,
What's your account type? Exchange, POP or IMAP?
According to my research, I'm afraid that there is no such a built-in option in Outlook to split a contact group. You may need to create a new contact group.
If you have more concern about this feature, I’d like to recommend you visit the Outlook user voice forum:
https://outlook.uservoice.com/ to vote for a similar idea or post your own.
>>1) What is the address limitation?
According to the information in
this link, for Exchange account, there is no definite limit to the number of contacts that you can add to a distribution list (A contact group is formerly called a “distribution list”). The exact limit is based on the total file size of the contacts. If
you use only the very basic information for contacts, your distribution list limit may be as many as 125 contacts to 130 contacts.
Hope this is helpful to you.
Regards,
Perry
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