Apologies if there's a thread for this already, or if I'm breaking other rules - if needed please admonish me and delete this thread.

I have been ringing the INZ call centre incessantly, with no success, and I have scoured their website to no avail, so I turn to ENZ for help. I would greatly appreciate any information regarding varying travel conditions on my Residence Class Visa. I am from the UK and received my Residence just over two years ago. My travel conditions expired on 22 August 2022, and obviously I started to look into obtaining PR. However, my UK passport expired in July 2022, something I hadn't realised having not used or even looked at my passport during the pandemic. Anyway, I have been dragging my feet a little when it comes to the laborious process of renewing a UK passport from overseas.

Fast-forward to now and a close family member has suddenly been taken gravely ill, so I need to get back to the UK. But with no valid passport, and the travel conditions of my visa expiring I am a bit stuck. I can get an emergency travel document from the British High Commission, which will allow me to travel without a passport : https://www.gov.uk/emergency-travel-document

Then, my question is: is it possible to apply for the variation of travel conditions using this document as opposed to a passport? I understand that the waiting period for the variation is currently 35 days, which may make the whole thing moot, but I have to see if it's possible.