Disable today even selectable by default

Hi,
I have a booking form using this plugin. My criterias:
– only two day by week to book : Saturday and Sunday
– only 11am to 2pm to book
– i disabled the today booking
–> Today, it’s sunday. I could click on the calendar field by default and don’t touch nothing but the hour and then the calendar displays 13-06-2021 11:00 (the today sunday date), and i can continue filling form and Send my message. Then i receive a booking email for today.
How that’s possible and how don’ have that ? I need that clients could ONLY book sunday and saturday, at least the day before.
I know that if i switch to another available day on my calendar, i couldn’t click again on the today day because it’s unavailable, but the problem is that if i DON’T chose the day, the default displayed is today.
Could you please help me with that ?
Thank you very much if you could ??

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