Likely to be revealed before the year is out, the Mercedes AMG GT 4-door rival will receive subtle revisions to the exterior look, including an altered tail-light design with an LED strip linking both units. The changes will bring it into line with newer Porsche models, such as the Cayenne and 992-generation 911.
Also evident on the latest prototypes is a new front bumper and reprofiled grille - but more significant is the introduction of new sensor modules at both ends of the front bumper. These indicate an advancement in the model's semi-autonomous systems could be on the cards.
Mechanically, Autocar understands Porsche is planning to introduce its first mild-hybrid powertrains for the Panamera. The S and 4S models will make use of the same 2.9-litre twin-turbo V6, but like US market versions of the Audi S6 and S7 the two variants are likely to adopt a 48V electrical architecture.