I wanted to import the AirBnB calendar via ical into my Google calendar but all the blocked days were annoying. Also the end date was one day too early on all events..
So i hacked a php snippet together which filters the “Not available” events and corrects the date. Then i simply added the php URL to Google calendar and now everything works fine!
If you want to use this snippet just replace the AirBnB URL with your own.