The factors that can affect shutdown event timing include the UPS battery availability, the storage system workload, and your company policies and procedures
If your UPS cannot support the default timing values, then your storage system will not be able to shut down cleanly.
If you have a large number of users, a large number of CIFS sessions, or any other workload factors that require a longer time to shut down, you need to increase the warning and critical time values to ensure that the system has sufficient time to shut down cleanly.
You may need to change the shutdown event timings to adhere to a protocol or requirement in place at your company.