Multiple Server Configuration - Master / Slave

I’ve not found anything to answer this anywhere and I realise its an unusual complex situation.

the closest but only partial answer is: Is it possible to cascade CMS Server?

I have a complex network of displays to manage across multiple sites.

Each remote site needs to be able to manage its displays.
Head office needs to be able to manage all displays and schedule content centrally.
The remote sites are not always connected to an internet / WAN connection.

Can Xibo be configured to have a local server at each remote site and Head office to have a master server which knows about all sites & displays and allows display content to be managed and scheduled (for download to the remote server & screens when a network connection is available).

What would happen when network becomes available if conflicting or just different changes were made on a remote server and master whilst offline?

thank you in advance.