Messages in iCloud behaviour I have 3 devices, on the MacBook, I have messages preference set to "keep forever", on the iPhone , I have it set to "delete after 30 days", and I have an older iPad, so its not up to date.

If I turn on messages in iCloud, whats going to happen?

Will the phone continue to delete after 30 days but allow the MacBook to keep forever? or will messages be deleted from iCloud after 30 days in accordance with the phone settings? 

or do all messages end up in iCloud regardless of those settings?
When one enables Messages in iCloud, iOS alerts you that the setting on the device will be changed to Forever. Forever is the only setting available when Messages in iCloud is enabled.



The goal of keeping all Messages in iCloud is that each device should sync up each and every message they have (some will have forever and all messages they received, some will have gaps and some will have duplicate messages).

You'll no longer back up any messages when you do an iCloud Backup. All participating devices will show the exact same set of messages.


  When you use Messages in iCloud […] your content is automatically stored in iCloud. That means they're not included in your iCloud Backup.