Thank you for your answers,
The Airbnb guest is staying with me for 10 days already and I just learnt about my upcoming visit. I do not like to upset people in general and of course guest neither. However, soon after I mentioned it, he sent me an email asking for a 30% refund deposited to his bank account. If he doesn't receive it by tomorrow he will go through Airbnb.
To be honest, if I was very keen on trying to not make him unhappy, I did not like his intimidating tone and specific request (which I consider too high). At this point, I wanted to understand which are my obligation in this respect and if (in case of partial refund) I should do it through Airbnb or by direct deposit.
Thank you for sharing your experience
Jean