Starting with the 2.8 Release, invalid for times got introduced. You can set it for certain days, daysOfWeek, Month, recurring days.
Example:
invalid: [
'1/1', // 1st of January disabled
'12/24', // Christmas disabled
'12/25', // Christmas disabled
'w0', // Sundays disabled
{ start: '00:00', end: '08:00' }, // Every day
{ start: '16:00', end: '23:59' }, // Every day
{ d: 'w6', start: '00:00', end: '08:59' }, // Saturday
{ d: 'w6', start: '17:00', end: '23:59' } // Saturday
]