Any change would have to accommodate a century of supporting evidence that we already have. So it's unlikely that it will change by a lot.
Or, to put it another way, cell theory is already extremely good at predicting cellular phenomena. We'd have to find some discrepancy that we've never observed in 100 years, and then we'd use that brand new evidence to modify the theory, so that the new cell theory would still make correct predictions about the last 100 years of tests we've put it through , and whatever the new test was.