Quote from AlmostGotIt:
It has to be opened and closed on the same day. The one from the day before wont count as a day trade because you held it over night. Opening a new trade doesnât count either, not yet I should say, its not decided until you close it... and caution on thinking you have 4 trades, you have 3, the 4th one is when they nail you... ie "4 or more" not "more than 4"