For 2024 Pilgrims: €50,- donation = 1 year with no ads on the forum + 90% off any 2024 Guide. More here. (Discount code sent to you by Private Message after your donation)
I just looked it up myself for my own planning so here you go! You should be fine for your flight time.
http://www.aena.es/csee/Satellite/Aeropuerto-Santiago/en/Page/1237554501825/Public-transport.html
Bus route running between the airport and Plaza de Galicia in Santiago, stopping at...
This site is run by Ivar at in Santiago de Compostela.
This site participates in the Amazon Affiliate program, designed to provide a means for Ivar to earn fees by linking to Amazon