Soft and hard booking
This feature is present since version 3.1.0 of the add-on and allows to book activity assigned to a particular user, or resource to which you cannot fully be sure about (e.g. user who doesn't have a valid job permit issued yet).
To use this new feature, create, or edit an already existing assignee activity. Hard booking, was the only possible one present up to 3.0.6 version of the add-on.
Since 3.1.0 version of the add-on, when following the typical way to create, or edit one gets a new feature "Soft-Booking" (1) present.
After getting it ticked, instead getting a standard hard booked activity, marked with full color filling (2), you ought to see diagonal stripes and white background (1):
Like in case of hard booking's solid background, stripe color is automatically set different for each activity. If an already existing hard-booked activity has been associated with i.e. green color then if you create a soft booked activity of the same type, color of the stripes is to be also set green:
Feel free to tell us what topic should be covered: staffingtimeline@psc-software.atlassian.net