Only Alex Albon has the updates this weekend, with Logan Sargeant having to wait until at least the next race in Austria before getting to run them.
The list of parts that have been changed includes the floor body, sidepod and engine cover bodywork. But there is also a revised mirror layout, a new halo fairing, new external geometry for the suspension fairings, rear brake ducts and rear wing endplates.
All of these have been fettled in unison in order that the various flow structures that are created by each surface can interact more effectively.
Given the scale of the changes, this is obviously not the work of a moment, as explained by head of vehicle performance Dave Robson:
"To get through the whole wind tunnel, aero development, design and manufacturing, it's a few months," he explained when asked by Autosport about the timescale of coming up with the revisions.
"Obviously, it's been a little bit tricky getting it through manufacturing, following the various repairs we've had to do since probably Melbourne".
Source: Autosport