Could the Royal Navy increase its strength mainly through additional Type 31 frigates?
Short answerProbably not mainly through Type 31s; they are valuable supporting escorts and presence ships within a mixed force.
NotesType 31 and related 30-series designs are expected to contribute to ship numbers, although the answer doubts a fleet expansion would be large enough to describe it as mainly Type 31s. The Type 31 role is to support assets such as Type 26, Type 45, and Type 83, including close protection for a carrier or amphibious ship. It also provides presence where the threat exceeds what would be suitable for a River-class patrol vessel. Type 32 is tentatively associated with controlling uncrewed assets. Separately, a proposed multipurpose vessel developed with Norway is mentioned as a possible replacement for patrol, oceanographic, and mine-warfare assets. Those possible roles remain unsettled.