The first Vega launch in 2019 is scheduled for 2019-03-14 carrying the Italian Space Agency’s PRISMA Earth observation satellite.
The Italian Space Agency’s Prisma satellite was planned for a 2018 launch but was delayed to 2019 due to delays with ESA’s Aeolus wind-mapping satellite.
The three missions that did not take place in 2018—the Arabsat-ISRO Ariane 5, OneWeb’s first Soyuz, and the Italian Space Agency’s Vega launch of Prisma—are on Arianespace’s 2019 manifest.