Hi @Glenn Maxwell ,
Agree with Andy.
In a distribution group, new members in March cannot see meeting invitations for January. But if you send the meeting invitation to the DL again, the new member will receive the meeting invitation.
The distribution group has an email address but does not have a mailbox, and only sends emails to members of the distribution list.
Unlike distribution groups, the Microsoft 365 group has shared mailboxes and calendars, which means that email is not only distributed to all members of the list but is also stored in separate mailboxes. Therefore, the new members will see the original meeting invitation.
For the difference between distribution groups and 365 groups, please refer to: office-365-groups-vs-distribution-lists
Please Note: Since the web site is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information.
Besides, if you want new members to see previous meeting invitations, you could upgrade the distribution group to a Microsoft 365 group.
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