You would leave the USA by Saturday, 2nd of September. 3rd of September with a transfer to your hotel:
The tour starts in SANTIAGO DE COMPO (SCQ)
NH Collection Santiago de Compostela.
Air Flights Sample
UA 140 2 SEP IAD BCN 5:40P 7:45A‡1
IB*5024 3 SEP BCN SCQ 12:50P 2:35P
UA 164 18 SEP MAD IAD 11:35A 2:30P
I can help with pre or post stays also.