By default, you will enter dates in your regional short format.  E.g. In the USA 12/31/2020; In Australia 31/12/2020.  This behavior is based on your browser settings, but to change it, go to ApeksOPS > Settings and alter the Short Date Format.

ApeksOPS displays dates in long format by default: e.g. June 5 2017.  You can have it display them in the short date format instead if you wish.  To do so, select “Yes” under “Display Dates Using Short Date Format”.