Hi Seb.
To introduce myself, I'm the product owner for Perform.
In short the answer is no. The appraisal is incomplete so that's the status it will express.
Some ideas.
I assume you are using the term 'appraisal' specifically and you are using a version prior to 13? If thats true then your choices are quite limited.
If you are using a TXP version of Totara (versions 13+), and you are using Perform, you do have an admin option to close incomplete performance activities at the due date.
I hope that helps.
Let me know if you have any questions or comments
Thanks
Phil