Well I suppose that would just be a further breach so the sanctions would ramp up. Who knows at what point they'd actually start getting banned from Europe, though.
Personally I think this assumption that City will be able to sidestep the FFP rules goes against all the evidence, not to mention reason. They and PSG have already received significant sanctions, just for a first offence. Other clubs have gone to the effort of becoming profitable. From the start, it's been made absolutely clear that any attempts to artificially inflate revenue won't be tolerated. So much for the evidence. Then there's the logic: why would Uefa go this far only to stop now? It doesn't make any sense to me.
That doesn't mean I think the likes of City will be made to stick absolutely to the rules, or that they'll suffer terrible consequences. They'll just be reined in a fair bit and be made to show willing, and for them, with the state of their squad, that'd be a real problem.