When a client views the booking page in the current month, the trailing dates of the following month are visible at the bottom of the calendar grid but appear greyed out — identical in appearance to unavailable dates. This causes clients to think there are no slots available in the next month, leading to drop-off or confusion before they realise they need to click the forward arrow to navigate.
A simple fix would be to either style those overflow dates to look selectable when availability exists, or add a small prompt such as "More dates available in [Month] →" to indicate that clicking forward will reveal slots.