=IF(tide<>"";
IFs(tide<TIMEVALUE("10:15");"--";
And(Tide>=TIMEVALUE("10:15");Tide<TIMEVALUE("11:00"));"Parking: 10:15";
And(tide>=TIMEVALUE("11:00");tide<=sunset-Timevalue("2:30"));"Parking: "& Text(Timevalue(round(tide*96)/96-"0:45");"hh:mm");
tide>sunset-Timevalue("2:30");"--")
;"")