diff --git a/erpnext/patches.txt b/erpnext/patches.txt
index f3660b3..9e022da 100644
--- a/erpnext/patches.txt
+++ b/erpnext/patches.txt
@@ -747,4 +747,4 @@
 erpnext.patches.v13_0.set_company_in_leave_ledger_entry
 erpnext.patches.v13_0.convert_qi_parameter_to_link_field
 erpnext.patches.v13_0.setup_patient_history_settings_for_standard_doctypes
-erpnext.patches.v13_0.add_naming_series_to_old_projects
+erpnext.patches.v13_0.add_naming_series_to_old_projects # 1-02-2021
diff --git a/erpnext/patches/v13_0/add_naming_series_to_old_projects.py b/erpnext/patches/v13_0/add_naming_series_to_old_projects.py
index 79b6753..5ed9040 100644
--- a/erpnext/patches/v13_0/add_naming_series_to_old_projects.py
+++ b/erpnext/patches/v13_0/add_naming_series_to_old_projects.py
@@ -4,23 +4,10 @@
 
 def execute():
 	frappe.reload_doc("projects", "doctype", "project")
-	projects = frappe.db.get_all("Project",
-		fields=["name", "naming_series", "modified"],
-		filters={
-			"naming_series": ["is", "not set"]
-		},
-		order_by="timestamp(modified) asc")
 
-	# disable set only once as the old docs must be saved
-	# (to bypass 'Cant change naming series' validation on save)
-	make_property_setter("Project", "naming_series", "set_only_once", 0, "Check")
+	frappe.db.sql("""UPDATE `tabProject`
+		SET
+			naming_series = 'PROJ-.####'
+		WHERE
+			naming_series is NULL""")
 
-	for entry in projects:
-		# need to save the doc so that users can edit old projects
-		doc = frappe.get_doc("Project", entry.name)
-		if not doc.naming_series:
-			doc.naming_series = "PROJ-.####"
-			doc.save()
-
-	delete_property_setter("Project", "set_only_once", "naming_series")
-	frappe.db.commit()