Additional chat-related features and issues within Microsoft Teams for business
Hi SynysterCraig91,
Thank you for posting on Microsoft Forum.
Based on your description, I understand that you want to know if an user who has been removed from a Teams group Chat would still see the change in that group. The answer is no; a removed user cannot see the group's modifications. When you send and then delete a message in group chat, it appears on the group that the message was deleted, not in group chat except for the owner.
However, When you delete a message you sent a long time ago with additional chat messages following it, there is no notification that the message was deleted. So, when you remove a user from a group chat, he is disconnected from that group; he will still see the conversation until the moment he was removed because all chat messages are already saved in his OneDrive, but he will not be able to see any changes made in the group, whether new message or deleted messages.
Looking forward to hearing from you.
Best Regards,
De Paul