What are the steps for mass update for employee work shift

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What are the steps for mass update for employee work shift

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Hi All,

Greetings!

This is about the requirement related to change of the employee shift from one shift to another (as part of work schedule assignment change). This change needs to be done effective from past date.

What are the available options to make this change?

We tried to mark the new shift as primary for the given legal employer but that did not change the shifts for employees from that legal employer.

Are there any ESS jobs or processes which needs to be run post the change?