diff --git a/docs/docs/user-guide/troubleshooting/update-not-installed.md b/docs/docs/user-guide/troubleshooting/update-not-installed.md
index 91d7f866..849b5c4b 100644
--- a/docs/docs/user-guide/troubleshooting/update-not-installed.md
+++ b/docs/docs/user-guide/troubleshooting/update-not-installed.md
@@ -28,4 +28,11 @@ installed. If the version number ends in `-fdroid`, you have the F-Droid version
 
 You cannot switch versions without uninstalling the current version first. First, backup your
 data in Settings > Backup & restore. Then, uninstall the current version and install the other
-version. You can then restore your data in Settings > Backup & restore > Restore.
\ No newline at end of file
+version. You can then restore your data in Settings > Backup & restore > Restore.
+
+::: warning
+The backup file format isn't guaranteed to be backward compatible. To ensure that all data is restored
+correctly, it is recommended to install the previous version first, restore the backup, then update to
+the latest version. For example, if you want to upgrade from `1.34.2-fdroid` to `1.35.0` (Github), install
+`1.34.2` (Github) first, restore the backup, then update to `1.35.0` (Github).
+:::