LDAP users from delegated directory cannot change their information though JIRA UI

When creating a "Internal with LDAP authentication" directory in JIRA, we have the message:

Configure Internal with LDAP Authentication User Directory

JIRA can use LDAP for user authentication only. To be able to log in to JIRA with this configuration, users must either be created first in JIRA, or the option 'Copy User on First Login' can be checked to automatically add them to JIRA's internal directory. Copied users can subsequently be modified in Confluence, but modifications will not be reflected on the LDAP server.

Groups and memberships from the LDAP server will not be used. However, users from LDAP can be added to groups maintained in JIRA's internal directory.

Let's say the user's info is the following:

• uid=testuser
• mail=testuser@ldapemail.com

If we try to change an attribute for one of the users in this delegated directory, for example, the email address (changing from testuser@ldapemail.com to testuser@jiraemail.com), next time the users logs in JIRA, the email address is set to the testuser@ldapemail.com.

This behaviour also can be observed by editing the user's Full Name.