Order's flag

Recently I have been noticing different flags flying from the buildings of the Order of St John.

On St John's Cavalier, the Embassy of the Order in Valletta, the flag has red background and the white eight-pointed Maltese cross; on Fort St Angelo the flag is a white cross on a red background and on Casa Lanfreducci, the headquarters of the Maltese Association of the Order in Valletta, the flag has a white Maltese cross on a red background. As far as I know the official flag of the Order of St John of Jerusalem, Rhodes and Malta is the one given by the Popes, especially Pope Innocent II, who in 1130 "ordinò che questa santa Religione Illustrissima milizia nelle guerre contro gli infedeli portassero lo stendardo con la croce bianca sul campo rosso" (ordered that this holy and illustrious Order in wars against the Infidels, bears the standard with a white cross on a red background).

May I ask what the official colours of the Order of St John are?