@Daniel0, I have some delays too and some of my responses just vanished. Three till now that I'm aware off, two way descriptions (they complained) and one quick answer to a request. I saw it on follow up 4 hours later and lost that booking.
One in-app answer and two mails. Not sure if one of them was not on the website.
Besides, the Community Center settings reverted to No Notifications all by themselves. I reset to "I want to read everything" and will see how long that stays (different wording, lol)
For your calendar idea: I import holidays into the Macbook / iphone calendar and can them switch on and off. That might help you till the airbnb programmer gets around to include thos comfortable function.