Given the changes in approach (everything being online), what is my best way to advise those organizing the interview of dates I cannot do. I have work out of the country from the 12th-20th December which I just can't miss. I therefore don't want to surrender my passport if it risks me not being able to leave the country.

Am I best to write a letter, or use the contact form? Or just pray? Has anyone had experience of trying to coordinate their interview even a little?

Appreciate that I have to accept a certain degree of 'its in their hands', but I also have a job to do.

Thanks for any advice

Send them a letter (signed for) with a copy of your online readiness notification and case number. Hopefully that should work.