We identified a bug in the multi-property calendar where the date headers and the availability grid can fall out of alignment when the calendar is scrolled horizontally. When they drift apart, the date label you see in the header no longer lines up with the cell underneath it, so clicking on what looks like June 5 is actually selecting an earlier date. The result is that the wrong date range gets passed to the booking page. Verify the dates shown on the property booking page before completing a reservation, and contact support if you see this on your site.