Keep in mind that Adelaide is located East of Spain, that means the sun rises first in Adelaide and later in Spain.
The azimut between Spain and Adelaide is 145°. Since an hour correspond to 15° the sun rises nearly 10 hours earlier in Adelaide than in Spain. So it is nearly midnight in Adelaide when the play starts in Spain. (Maybe you should get some informations about the correct time zones)
As I've posted you can use the property: 1° on a great circle correspond with 60 nm (=60'). Since the yacht sails on a great circle it has covered the distance of 15° = 900' = 900 nm.
Now convert the nautical miles into kilometres if necessary:
Therefore the yacht needs:
Convert into days and hours and calculate the date and time of the arrival.