No, that is not correct. ITS#7274 was invalid, and had to do very specifically with the way in which I wrote a script to promote a stand-alone master to MMR mode. It does not apply to your situation. More likely, you would be hitting http://www.openldap.org/its/index.cgi/?findid=7849.
--Quanah
Right. With openldap-2.4.40 the issue did not appear again: everything fixed.
thank you,
Francesco