No, EC didn't say that they expect big improvement, only to be in front of the middle pack.
The big expectation is the confirmation that they are going in right direction with the development linked with 2021 spec of the car.
PS I am a long time Ferrari fun and I desperately want to be at least in battle with RB but with this PU no. We have to wait for the next season. They said that PU has a big improvement but also we do not know what MERC will bring (there are rumors for revolutionary intake plenum), I hope Cavalino Rampante also have some ace up in the sleeve
PS Sorry for my bad English it is not my native (I am from Macedonia)