Originally Posted by Infinity9999x
The major issues lie with this: We see a walking older Charles Xavier, which would be impossible, given that since FC is supposed to definitely be cannon, Charles was injured as a much younger man.
Ya, we see that in X3 aswell. We also see many contradictions between First Class and X1 and X2... so continuity being poor is not an excuse to completely ignore a movie from a franchise. If that were the case then none of the movies would have gone together... except maybe X-men 1-3... and I'm sure X3 has some contradictions.