diff --git a/docs/administration.rst b/docs/administration.rst
index c2ca7b04..9f4d47d5 100644
--- a/docs/administration.rst
+++ b/docs/administration.rst
@@ -871,6 +871,15 @@ account. See :ref:`Using a pre-existing ACME account <AcmeAccountReuse>` for mor
 
             This is the registration for the ACME account, the most important part is the uri attribute (in JSON)
 
+.. data:: ACME_PREFERRED_ISSUER
+    :noindex:
+
+            This is an optional parameter to indicate the preferred chain to retrieve from ACME.
+            This is applicable to Let's Encrypts recent `migration https://letsencrypt.org/certificates/`_ to their own root where they provide two distinct certificate chains;
+            the main chain will be the long chain that is rooted in the expiring DTS root, whereas the alternative chain is rooted in X1 root CA.
+            Select "X1" to get the shorter chain (currently alternative), leave blank or "DST Root CA X3" for the longer chain.
+
+
 Active Directory Certificate Services Plugin
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~