My predictions, given the patterns of the most recent updates and Kaz's car choices (four cars):
Honda Vezel Hybrid Modulo X '19 - Kaz has begun to add new SUV's (starting with the Lamborghini Urus), but he has also included economy crossovers, and given that vehicles such as the Toyota C-HR, Mazda CX-30 and Suzuki Jimny Sierra have been added lately, the Honda Vezel Hybrid Modulo X (HR-V in other countries) would make sense.
Hyundai N Vision 74 '22 - Given Polyphony's strong partnership with Hyundai even after the official Manufacturers Cup partnership with Genesis has ended, the N Vision 74 would be ideal for the next update, to celebrate the Hyundai N brand, and that a real RC version of this car is a reward for winning a Hyundai-sponsored time trial event.
Koenigsegg Jesko Attack '21 - If Kaz still won't add a race car this time around, he could at least add one car that's surely going to provide some positive feedback with this update, with the Koenigsegg Jesko Attack, scratching the itch for the hypercars and exotics crowd and finally giving in to the fans' demand for Koenigsegg to be featured. Also to make up for adding the Renault Kangoo from the previous update, and not to mention, even if it may be a long shot, it could be a fitting rival to the Aston Martin Valkyrie.
Subaru Impreza Sedan WRX STI '10 - Ever since day one of the game, a 3D model of this car was always seen in GT Auto, but never seen in actual gameplay as a fully complete car. It is apparently on the datamine, however, and one more Subaru won't hurt.
No new track, however, expect GT Sophy support to be expanded, as well as new engine swaps, Scapes and race events.