A few issues are remaining, and will likely need to be fixed after release 3.0 (3.1 or later):

Here is the list of issues which were mentioned in #14602:

• Add a way to configure all ldap_set_option entries.
  • Dereferencing
  • Timeout
  • Debug level
  • ...
• Handle multiple connections

I'm separating all these from the current PR (#15994), as I am currently the only person working on the LDAP component on a regular basis, and won't have time to handle these remaining features for Symfony's 2.8 / 3.0 releases.