Bulk Replace an Approver in Multiple Approval Groups

Log in to the Production with your Admin account

Navigate to Setup > Approval Setup

Click the 3 dot menu on the right and select Bulk Change

Select the people from the dropdown lists for Old Approver and New Approver.

Then select the modules that you want the change applied to. You can select multiple modules.

Then click the Save button.

You will get a green success message.

This means that both the approval group/s and any pending approvals in flight have been updated to the new approver.