There is nothing to 'meet'...
They have only to demonstrate a move towards improving - which they will do, with some ease.
As others have said, they'll lose a couple of high earners, plus they'll have increased revenue from winning CL which should just about cover their two new signings.
Next year they may be a little more frugal which will only serve to demonstrate even more of a move 'towards' sensible expenditure.
FFP is really designed to stop clubs being in danger of going under, rather than putting off rich spenders (although I suspect Chelsea and City are flies in the ointment for UEFA).
And, let's also remember that 'sanctions' are a last resort in FFP, not the first line of action.