So instead of facing the situation where an adapted car is being discussed in 4 separate topics, I'd figure to centralize the whole deal. We are going to have more tests with different adaptations, which will only be allowed to be discussed in this topic.
The current 'agreement' is to run 2015 cars adapted to be able to drive wider 2017 tyres, as well as run 2017 downforce levels. However, in order to give none of the 3 testing teams a distinctive advantage, the adapted aero devices are not allowed to comply with the 2017 rules. So they are only allowed to run a similar downforce level, but the changes to bodywork have to differentiate enough to 2017 tech rules.