LDAP: usernames change, how to keep nbextcloud account & shared links

Nextcloud version (eg, 12.0.2): a slightly actual one
Operating system and version (eg, Ubuntu 17.04): RHEL
Apache or nginx version (eg, Apache 2.4.25): dont know
PHP version (eg, 7.1): dont know

In our LDAP directory service, the email addresses and thus also the user names (cn) will soon be changed. Our Nextcloud admins say that new user accounts will be needed in the Nextcloud, and we will have to download all our data in order to transfer it to the new user. What bothers me is that all my shared links will then be gone.
Is there any way to avoid that?

keiner der sich bezüglich Nextcloud mit LDAP auskennt?

nobody who knows LDAP regarding Nextcloud?

You can transfer data to a new user via occ-command, but I’m not sure if shares and external links are preserved, can be verified with a test user or ask clarification in the docs (https://github.com/nextcloud/documentation/issues):