In this video, The Race explains haas' infamous rear suspension problem and what could be causing it. Now, that aside, what's the important bit here is that haas buys its suspension components from Ferrari
I'm positive Ferrari faces the same problem.
It all adds up, 1. With the general complaints all thru the season, of the balance being all over the place, especially in the rear. 2. Ferrari later clarifying with a statement that they "discovered a tuning fault in the rear hydraulic suspension", which they "corrected" (this was around the Russian/eifel gp i think). 3. Focus on rebuilding the rear suspension for 2021. This is one big --- up from the team. I don't believe in the 'revolving doors' policy, but that one guy who designed this must be fired.
Hats off to Leclerc tho. If this is true, his performance is legendary.