The EdA has roughly equal numbers of F18s and Typhoons, replacing the former solely with more of the latter is a bit eggs in one basket. The Armada's website page for its LHD Juan Carlos I describes it as having the "Capability for up to 30 medium and heavy helicopters for amphibious operations or 10/12 F-35B or AV-8B+ and similar number of helicopters in her aircraft-carrier configuration." So it's pretty clear what the FLOAN wants/needs if it is to carry on fixed wing operations.
However I thought the NGF to be developed under FCAS was planned to replace some, if not all, of the EF-18s. So, is this to prevent a capability gap between c.2030 and the 2040s or a public expresion of a lack of faith in FCAS delivering? Or a desire for a proven technology that, assuming they go for a common B model procurement, one assumes will benefit from USMC/RAF etc. future enhancements.