@Sudsrung0 Yes, the calendar on the other website is open. I also called the support of the other website to have it confirmed. Today the other website is blocked for an extra day: November 9-12> this confirms the idea that Airbnb only sends reservations for the next 365 day
@Bob297 Check your availability settings. On AirBnB, my calendar is open only for 12 months. I checked the other sites that I book through (like VRBO) and made sure that the calendars on those sites are open for the same time period as my AirBnB calendar.
Calendar syncs are governed by the shortest settings -- i.e., if one calendar is only for a year and cannot be changed or does not synchronize to a longer time period, all of your calendars should be for the same length of time or slightly shorter. I hope that this helps.