diff --git a/erpnext/hooks.py b/erpnext/hooks.py
index fba886ca2c..dbfbcc9b38 100644
--- a/erpnext/hooks.py
+++ b/erpnext/hooks.py
@@ -356,7 +356,7 @@ auto_cancel_exempted_doctypes = [
 
 scheduler_events = {
 	"cron": {
-		"0/5 * * * *": [
+		"0/15 * * * *": [
 			"erpnext.manufacturing.doctype.bom_update_log.bom_update_log.resume_bom_cost_update_jobs",
 		],
 		"0/30 * * * *": [
diff --git a/erpnext/manufacturing/doctype/bom_update_log/bom_update_log.py b/erpnext/manufacturing/doctype/bom_update_log/bom_update_log.py
index c3f52d4583..51f7b24e74 100644
--- a/erpnext/manufacturing/doctype/bom_update_log/bom_update_log.py
+++ b/erpnext/manufacturing/doctype/bom_update_log/bom_update_log.py
@@ -212,7 +212,7 @@ def resume_bom_cost_update_jobs():
 			["name", "boms_updated", "status"],
 		)
 		incomplete_level = any(row.get("status") == "Pending" for row in bom_batches)
-		if not bom_batches or incomplete_level:
+		if not bom_batches or not incomplete_level:
 			continue
 
 		# Prep parent BOMs & updated processed BOMs for next level
@@ -252,6 +252,9 @@ def get_processed_current_boms(
 	current_boms = []
 
 	for row in bom_batches:
+		if not row.boms_updated:
+			continue
+
 		boms_updated = json.loads(row.boms_updated)
 		current_boms.extend(boms_updated)
 		boms_updated_dict = {bom: True for bom in boms_updated}
diff --git a/erpnext/support/doctype/service_level_agreement/service_level_agreement.py b/erpnext/support/doctype/service_level_agreement/service_level_agreement.py
index 7f4e9efa94..2a078c4395 100644
--- a/erpnext/support/doctype/service_level_agreement/service_level_agreement.py
+++ b/erpnext/support/doctype/service_level_agreement/service_level_agreement.py
@@ -13,8 +13,8 @@ from frappe.utils import (
 	get_datetime,
 	get_datetime_str,
 	get_link_to_form,
+	get_system_timezone,
 	get_time,
-	get_time_zone,
 	get_weekdays,
 	getdate,
 	nowdate,
@@ -981,7 +981,7 @@ def convert_utc_to_user_timezone(utc_timestamp, user):
 
 
 def get_tz(user):
-	return frappe.db.get_value("User", user, "time_zone") or get_time_zone()
+	return frappe.db.get_value("User", user, "time_zone") or get_system_timezone()
 
 
 @frappe.whitelist()
diff --git a/erpnext/utilities/doctype/video/video.py b/erpnext/utilities/doctype/video/video.py
index 13b7877b21..62033a5e18 100644
--- a/erpnext/utilities/doctype/video/video.py
+++ b/erpnext/utilities/doctype/video/video.py
@@ -10,6 +10,7 @@ import pytz
 from frappe import _
 from frappe.model.document import Document
 from frappe.utils import cint
+from frappe.utils.data import get_system_timezone
 from pyyoutube import Api
 
 
@@ -64,7 +65,7 @@ def update_youtube_data():
 
 	frequency = get_frequency(frequency)
 	time = datetime.now()
-	timezone = pytz.timezone(frappe.utils.get_time_zone())
+	timezone = pytz.timezone(get_system_timezone())
 	site_time = time.astimezone(timezone)
 
 	if frequency == 30:
diff --git a/erpnext/www/book_appointment/index.py b/erpnext/www/book_appointment/index.py
index dfca9465ed..f50c207ab9 100644
--- a/erpnext/www/book_appointment/index.py
+++ b/erpnext/www/book_appointment/index.py
@@ -4,6 +4,7 @@ import json
 import frappe
 import pytz
 from frappe import _
+from frappe.utils.data import get_system_timezone
 
 WEEKDAYS = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday"]
 
@@ -125,7 +126,7 @@ def filter_timeslots(date, timeslots):
 
 def convert_to_guest_timezone(guest_tz, datetimeobject):
 	guest_tz = pytz.timezone(guest_tz)
-	local_timezone = pytz.timezone(frappe.utils.get_time_zone())
+	local_timezone = pytz.timezone(get_system_timezone())
 	datetimeobject = local_timezone.localize(datetimeobject)
 	datetimeobject = datetimeobject.astimezone(guest_tz)
 	return datetimeobject
@@ -134,7 +135,7 @@ def convert_to_guest_timezone(guest_tz, datetimeobject):
 def convert_to_system_timezone(guest_tz, datetimeobject):
 	guest_tz = pytz.timezone(guest_tz)
 	datetimeobject = guest_tz.localize(datetimeobject)
-	system_tz = pytz.timezone(frappe.utils.get_time_zone())
+	system_tz = pytz.timezone(get_system_timezone())
 	datetimeobject = datetimeobject.astimezone(system_tz)
 	return datetimeobject