On which Portuguese island has the largest European airline by scheduled passengers flown had a base since 2015?
João Paulo II Airport: João Paulo II Airport (IATA: PDL, ICAO: LPPD) , named after Pope John Paul II, is an international airport located on the island of São Miguel, in the Portuguese archipelago of the Azores. João Paulo II Airport:  The airport is the major hub for the SATA Group of airlines, which includes both inter-island SATA Air Açores and international Azores Airlines, and since April 2015 as a base for Ryanair.
i don't know