Why would I ever use calc? As explained in https://taskwarrior.org/support/faq.html#q9:
That
due-2daysvalue is evaluated by Taskwarrior, using the value you specified for the due date and subtracting two days. You can also verify that date using thecalccommand:$ task calc eom-2days 2018-01-30T00:00:00
That makes setting recurring waits, because I want them to show up when I am ready, not when they are due…
task add priority:L due:eod recur:daily wait:due-6h Log daily activities
That makes a low priority (still higher than default) due at the end of each day, and waits until 6PM to show it on my next list.