The new HART fleet are starting to roll out in England & Wales.
Each team will have five Incident Response Units, on MAN chassis with a box body functionally similar to the secondaries and replacing both them and the primaries.
There's an additional Hilux for each team, also badged as an IRU which isn't a PRV and is supposed to be used to provide off-road capability in addition to the Polaris.
I don't know if anyone has quite decided how they'll be deployed (with the old units, a team would be typically split into two pods with a primary & secondary each).
Is it too much to hope the devs are going to update the HART mechanic in the game?