How to update the meals rate in the per diem policy if the policy is currently active?

Summary:

We have an existing per diem policy in place; however, the company changes the per diem rate every quarter. Is it possible to add and "End date" in the spreadsheet of the existing per diem rate and add a new row to capture the changes. Only the rate changes quarterly and not the geography location. We tried to update the meals rate but it's throwing an error that it is protected.

Content (please ensure you mask any confidential information):

Refer to the column wherein we try to update it but it's not capturing the rates correctly.

Version (include the version you are using, if applicable):