I have a whassap group with 4 other work colleagues. The work group dates back to Nov 2018. One of the members from the group had broken there phone and got a new one, so on there new phone the chat only dated back to April 2019.
If someone airdropped this chat and emailed it to themselves from her phone with the chat dating back to April would they be able to retrieve the rest of the chat dating back to Nov from this file they have transfered. Baring in mind this person didn't have permission to do this ?
Who would they need permission from? Either they can do it or they cant! If they have the chat history since November, it looks like they can do what you are asking! Perhaps you need to address the permissions issue with whatsapp. Good luck with that, the parent company is facebook and we all know how well they support their users!!!!