you must finalize your orders

At the time the turn ends, the last set of updated moves will be acted on.

The will definitely go through so long as click update. Often players don't get around to putting their moves through on time and end up wasting a turn (with all units holding). If you are not certain what moves you want to make, I suggest putting in some provisional moves and clicking update, but not finalize until you are certain. That way if the end of phase arrives and you haven't had a chance to review your moves at least your units will do something, which is usually better than nothing.

In some of the upper level games particularily the league games the moves are never finalised to facilitate maximum press.