NetSuite updates twice yearly. These releases are obviously important to maintain constant development. However, they can occasionally cause disruption or take place at awkward times. We see some global clients receive a scheduled upgrade time that is perfectly fine in their own time zone but hugely disruptive for their subsidiary in another time zone - so it's essential for some companies to re-schedule upgrades to take place over the weekend.

When the upgrade is imminent, it will show in your NetSuite dashboard. Following the link to further details about the upgrade will show more information (like so). 

Upgrade settings are also accessible via the setup menu (Setup > Company > Customer Scheduled Maintenance).

Whilst most upgrades run smoothly, we have seen occasions when unexpected behaviour is created in NetSuite during these upgrade periods. Issues are typically temporary but can have business impact. Such unexpected behaviours have included unexpected errors (no stacktrace), undeployed scheduled scripts running when they shouldn't and issues around SuiteApps.