With how Intervals currently works tasks can be sorted by any of the column headings. For example, to sort by task number, click the “#” at the top of the list. Clicking again will filter the list in the opposite direction.
Currently Intervals does not support a second sort order, but by default the second sort order is the task number.
Finally, when the task list is filtered and re-sorted, the task list sort order will be remembered. This allows you to navigate away from the page and come back with the same ordering in place. This also gives you the ability to create saved filters with different sort order preferences.