Fuel...
They're saying that Oporto LPPR has a direct pipeline to feed the airport, leaving LPFR (Faro) and LPPT (Lisbon) without Jet A1 because it’s supplied by tanker trucks. Same trouble also affects LPCS (Cascais) with Jet A1 only available to medical evacuation helicopters.
If you're going to fly there, better check your fuel gauges.