In general, the "Reserved item" option in the first dropdown (the subcontext) is split up into 3 options.

This reserved item
At least one reserved item
No reserved items

This reserved item

Only available in (main) context "Reserved item".
Looks at the reserved resource in which the change happens.
Behaves like the old situation where every reserved resource is compared to the condition.

At least one reserved item

Looks at all reserved resources but only checks if reserved resource complies with this condition.

No reserved items

Looks at all reserved resources but only checks if reserved resource complies with this condition.

As seen in the screenshot at the top of this comment, it is possible to nest conditions.
This is only possible for At least one reserved item or No reserved items.
All nested rows will be criteria the reserved items will have to comply with.
For example: At least one reserved item should be of accommodation kind Villa and it should have a start date (arrival date) later than a specific date.

Legacy fallback

Older conditions with the "Reserved item" subcontext will still work. When opened, it will display "Reserved item" instead of one of the 3 new options. But the option is disabled in the dropdown and won't show as soon as another subcontext is chosen. It can also not be selected when creating a new condition.

Notification delay

Per condition, a delay can be configured. This gives extra time to organize a reservation before an email/sms is send out. If the same or another condition of the task is triggered in the meantime, the delay will be adjusted. When the delay has elapsed, the condition is re-evaluated. If the reservation still meets the condition, the actions will be executed. Even if the condition has been triggered multiple times, the actions will only be performed once.

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