Lock or Flag Invoices After Export to Xero

Once an invoice has been finalised and exported to Xero, I believe it should be locked from further edits (similar to payments), or it should indicate somewhere on the invoice screen that it has been exported. There doesn't currently seem to be a clear indicator to show if an invoice has been exported yet. This would prevent accidental amendment by team members that aren't involved in the exporting, so would be unaware that the invoice has been exported. 

That way if an amendment is required after the export, the appropriate process to credit the invoice and then re-invoice it would have to be followed.