Hello Pecoflyer.... you haven't abandon this have you ?

I can agree that Excel changes the entry to "short date", as that's what shows in the formula bar.
It makes no sense that Excel change the entry to "short date" as per Regional settings and then not display it as such.
Where did Excel get the decision to display the date as 3-Sep-18, that's neither what was entered nor what Excel changed it to ?

Is there a setting somewhere within Excel or Office that sets a default date display ?

Should this thread be moved to the Office sub forum to maybe catch others who might have an explanation as to why Excel is doing this ?