Based on examples, the answer is no.
The reason for this request is that I am creating a GANTT chart for a whole year and using 'projectscale weekly'. However, looks like I can not get plantuml to draw the last days of the year without having a task that extends over the holidays from Christmas to New Year - something I want to avoid.
Is there a way of doing it in current plantuml?
If not, syntactically, adding 'project ends 2021-12-31' should suffice.