FYI, there's NO integration between CUPS and LDAP.
CUPS get the users and authentication for them via AXL, from whatever you have in CUCM. So, you do have the authentication for your users to LDAP.
The default configuration is that, you will use the SRV records and bind to LDAP for contact resolution.
No, they don't get the info from what you have on CUCM, nor this is an issue, this is WAD.
If you want to change to what field J4W syncs, or the directory integration, it's all explained in the J4W install and configuration guide under the chapter "Configure Cisco Jabber", modify the jabber-config.xml as required in your environment.
HTH
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