Class One. The question: why speak of Yetzias Mitzrayim after Moshiach comes, since that redemption will be much higher? Answer One: Because there is some similarity, as both are connected to revealing the 50 gates of Bina (but not on the same levels). Answer two: Because all Geulos -freedom- begins with Yetzias Mitzrayim and it gives the power to all Geulos that will follow.
Class Two Answer Three: Yetzias Mitzrayim was Iskafia and the final Geulah is Ishapcha, there will remain an advantage in Iskafia even when Ishapcha predominates.