State exactly what approval freezes and check the report first.
Approval is a control point, not a formatting button.
Choosing Approve opens a warning: after approval, KPIs and time ranges cannot be changed. The dialog offers Approve and Approve & Send. After sending, only recipients can be edited.
Before approval, verify the report period, KPI selection, comparison basis, section order, commentary and recipients. If any of those are still uncertain, cancel and return to the draft.
1The warning text — read this before clicking through
2Approve, and Approve & Send, as two separate buttons