It all depends on who leaves I think. We've got 6 CMs and I'd group them on likelihood of being kept/sold like this:
To stay: Bentancur, Ramsey, Matuidi (50-50 I'd say)
To go: Khedira, Pjanic, Rabiot
Now, in the most extreme scenario we could offload even 4 CMs. Realistically we'll get rid of...