RefundStatus

Created, not sent yet. It can be changed, sent or deleted.

The last attempt to send it failed; 'lastErrorMessage' says why. It can be changed, sent again or deleted.

Accepted by the payment provider or the bank. It can no longer be changed, sent or deleted, except for its internal note.

The outgoing transaction of the payment provider or the bank has been imported and matched to the refund, normally after it was sent. Like a sent refund it can no longer be changed, sent or deleted, except for its internal note.