Transformers 6 and 7 Are Deep in Story Development
It looks like Paramount are planning well ahead, as all studios do now, with its Transformers franchise. Outlines have reportedly being penned for film's six and seven in the franchise, though scripts haven't been started given that the next film is not even out yet.
The Last Knight is essentially a sequel to Age of Extinction, which itself launched something of a new saga for the franchise. Confirmation of films 6-8 came during production on The Last Knight.
Expect more of the same really, in the franchise that proves that artistic merit does not need to exist for a film franchise to reap the rewards of the blockbuster market.