diff --git a/scripts/upgrade b/scripts/upgrade
index dac6b85..45ad50e 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -15,6 +15,29 @@ source /usr/share/yunohost/helpers
 
 upgrade_type=$(ynh_check_app_version_changed)
 
+#=================================================
+# ENSURE DOWNWARD COMPATIBILITY
+#=================================================
+ynh_script_progression --message="Ensuring downward compatibility..."
+
+# If fpm_footprint doesn't exist, create it
+if [ -z "${fpm_footprint:-}" ]; then
+	fpm_footprint=low
+	ynh_app_setting_set --app=$app --key=fpm_footprint --value=$fpm_footprint
+fi
+
+# If fpm_free_footprint doesn't exist, create it
+if [ -z "${fpm_free_footprint:-}" ]; then
+	fpm_free_footprint=0
+	ynh_app_setting_set --app=$app --key=fpm_free_footprint --value=$fpm_free_footprint
+fi
+
+# If fpm_usage doesn't exist, create it
+if [ -z "${fpm_usage:-}" ]; then
+	fpm_usage=low
+	ynh_app_setting_set --app=$app --key=fpm_usage --value=$fpm_usage
+fi
+
 #=================================================
 # DOWNLOAD, CHECK AND UNPACK SOURCE
 #=================================================
@@ -36,7 +59,7 @@ chown -R $app:www-data "$install_dir"
 ynh_script_progression --message="Upgrading PHP-FPM configuration..."
 
 # Create a dedicated PHP-FPM config
-ynh_add_fpm_config
+ynh_add_fpm_config --usage=$fpm_usage --footprint=$fpm_footprint --phpversion=$phpversion
 
 # Create a dedicated NGINX config
 ynh_add_nginx_config