No. I suspect that they were both speaking of leaven in the same sense that the Jews did (and it was the same reason that the leaven was left out of the Passover Seder as well). And yet the Passover feast was still a real feast, no? The leavening (our sin I believe) was left out. But it was left out of real bread as well, not just metaphorically. How does your point change the tie between Passover and Easter? The verse is still "Christ: Our Passover Lamb"
Here is Jesus on the Jewish feast day calling them to come to him and drink. Imagine the significance of this statement in light of the passover. In other words, don't go to the Jews and their feasts, come to me and drink. He didn't last long after this. He taught them to eat and drink him, when some left him for that saying. He is the fulfillment of passover and to look to an empty ritual is ignorance of the truth.
John 7:37 In the last day, that great day of the feast, Jesus stood and cried, saying, If any man thirst, let him come unto me, and drink.
38 He that believeth on me, as the scripture hath said, out of his belly shall flow rivers of living water.
39 (But this spake he of the Spirit, which they that believe on him should receive: for the Holy Ghost was not yet given; because that Jesus was not yet glorified.)
Here is Paul teaching of what to do if you are asked to a feast by an unbeliever and only if you are disposed to go, not even a requirement and not any feast held within the church.
1 Corinthians 10:27 If any of them that believe not bid you to a feast, and ye be disposed to go; whatsoever is set before you, eat, asking no question for conscience sake.