Extra time with addons removes some bookable slots

[Valentina R]

Easy to reproduce to create a product with Inventory of 9, availability daily 9:00 - 21:00, duration 90 min, interval 30 (or 120) min, padding, of 30 min. Quantity addon with adjusted duration “Quantity based: 120“.

Then go and book the slot at 11:00 7 times and the slot at 13:00 7 times. Now, both those slots are still availbale 2 times and can be booked for the default duration. But as soon as you select the addon to add 2 extra hours, the slot at 11:00 is removed (not available).

Reported here.