I'm a host can I cancel a booking 6 month in advance

Hi

Simply yes , but the trick is to do it by :  

1. Notify the Guest first, "Hi I am reaching out to you to notify you that your booking in july will be cancelled due to the property is no longer  taking bookings, and will not be operating at your booked dates also. You will short ly receive a system notification for cancellation, please ensure to click the link in it so the system can expedite the process and if any prepaid amount will then start process to refund it to you , asap. "  
2. Dont pad it out, stick to the point , dont overshare. They dont need to know the Cat's mother's 2nd cousin has died.  
3. Should on rare occasion the guest decide to not reply then you can cancel it in a slightly different way. by using option 1 instead of option 2 , typically used for when a deposit is not prepaid.  
4. Should guest reply and or contact BdC CS to ask about changing dates and to another listing, you might end up with relocation invoice, but this is why its better to talk directly to the guest. In this case 6months notice is loads so they should not be unreasonable.  
5. Right now you have notified them, straight away go to the reservation details page, on right pane... click Request Cancellation.  
6. Most of the time you will choose option 2 and then the system notifies the Guest, and they must click to confirm.   
7. Wait for guest to make the action, then system will notify you when they do and mark as cancelled.

This has worked for me everytime.

Kind Regards