Do you really think it was a big suprise given LH engine Penalty?
For me, the only way LH retains the lead is if something bad happened to Max in Turkey, and it didn't. What maybe should have happened was instead of 6 points, the gap would be 1 or 2 in Max's favour.
As for the car.. It's hard to tell if they have gotten weaker and Mercedes stronger. What is clear is the Ferrari and Mercedes engines are stronger at this stage than the Honda units. The setup on the RB16 is showing the same issue, understeer that Max does not like, but comes towards Perez.
It's anyone's guess what happens at COTA. If it's dry I think a podium for both can happen again. I do not know how well Bottas drives there.
The dark horse is Ferrari again, and maybe Mclaren.