diff --git a/README.md b/README.md
index 1aad887..b2b9c37 100644
--- a/README.md
+++ b/README.md
@@ -7,6 +7,13 @@ edition. Currently this repo uses sharelatex:latest.
 The inital idea for this implementation was taken from 
 [worksasintended](https://github.com/worksasintended).
 
+# BREAKING CHANGE
+be careful if you try to migrate from 3.3.2! Backup your machines and data.
+The migration paths hould be:
+- Backup Your machines and Data
+- run latest 3.5 sharelatex image and run the migration scripts
+- run this sharelatex image (4.1.1) and run the migrations scripts
+
 
 ### Limitations:
 NEW: This version provides the possibility to use a separate ldap bind user. It does this just to find the proper BIND DN and record for the provided email, so it is possible that users from different groups / OUs can login.