diff --git a/scripts/upgrade b/scripts/upgrade
index cdd42ea..9423cc2 100755
--- a/scripts/upgrade
+++ b/scripts/upgrade
@@ -201,10 +201,12 @@ ynh_add_nginx_config
 
 # Define a function to execute commands with `occ`
 exec_occ() {
-    # Backward compatibility to upgrade from NC14 or older version
-    if [ $current_major_version = "last" ] || [ $current_major_version -ge 15 ]
+    # Backward compatibility to upgrade from older versions
+    if [ $current_major_version = "last" ] || [ $current_major_version -ge 20 ]
     then
         NEXTCLOUD_PHP_VERSION=$phpversion
+    elif [ $current_major_version -ge 15 ]
+        NEXTCLOUD_PHP_VERSION="7.4"
     else
         NEXTCLOUD_PHP_VERSION="7.0"
     fi