Keep the diary honest about who's actually available, so nobody books over someone's time off by mistake.
In Day view, tap + Add Booking, then Block time off. Choose a type (holiday, sick, appointment, training, or other), the worker it applies to, the day, and a time range. Confirm, and that time shows up in their lane as a hatched block rather than a normal booking, clearly not something to try booking over.
Time off always belongs to a specific person, so it needs a real worker chosen, not the Unassigned lane. If you land on Unassigned when you open the block flow, you'll be asked to choose someone before it can be confirmed.
Booking or moving something into a worker's blocked time still shows a warning first, the same as double-booking two jobs would, rather than silently refusing. That way a genuine exception (a quick job squeezed in around a morning appointment, say) is still possible, but never by accident.
Questions: hello@tradeflow365.com.