No we had to wait until Ds2 finished the school year. 
Plus Ds had to attend his sixth form induction day which was around 10th July and this was part of the condition of them accepting you on results day.
So our holiday had to fall after the end of July and before results day by a good few days in case we needed to row across the Atlantic ocean to get back in time for results 
But we can do it when Ds2 finishes his GCSEs as Ds1 will be at uni so should also finish mid June, hooray!