^The EU press release says the 2.0 model will go on sale in March, so SOP for a new model year should just be around the corner.
https://www.supramkv.com/threads/toyota-europe-announces-first-extension-of-the-gr-supra-sports-car-range-w-new-2-0-turbo-engine.3191/
Edit: Just read up on the...