I've taken to tagging my tasks with times, and here's some code to
automatically sort tasks by time, status, and priority. I use it on
day pages. My plan pages are sorted differently. =)

I could go on and on about how powerful customizable task sorting
functions are. Kudos to Jody Klymak and John Sullivan for suggesting
this last December! It's one of the things I love about planner. =)

(defun sacha/planner-sort-tasks-basic ()
  "Sort tasks by time (@1030, etc), status (_P>XC) and priority (ABC)."
  (let* ((info (planner-current-task-info))
         (status (aref (planner-task-status info) 0)))
    (concat
     ;; time
     (or (and (string-match "@[0-9][0-9][0-9][0-9]" (planner-task-description info))
              (match-string 0 (planner-task-description info)))
         "@9999")
     ;; status
     (cond
      ((eq status ?o) "1")
      ((eq status ?P) "2")
      ((eq status ?>) "3")
      ((eq status ?X) "4")
      ((eq status ?C) "5")
      (t "9"))
     (planner-task-priority info))))

See my planner-config.el for my
complete task sorting code and lots of other config stuff. =)