The day of the week of the current year’s Jewish Passover-- which is celebrating entirely different events-- is not relevant to the Pascal Mystery.
I agree that the calendared dates are “off,” but are you saying that there is no correlation between Moses leading the Jews out of physical bondage and Jesus, who led mankind out of spritual bondage?
Are you saying that there is no Old Testament prefigurement and are you denying that during the Last Supper, Jesus predicts his slaughter as the ultimate Passover sacrifice, the sacrificial lamb?
The Jews have kept their Passover, but it has much to do with the Paschal Mystery.
OP, please see the
about.com article by N.S Gill titled ’ Dating Easter: Passover vs Easter Dates’ located here:
ancienthistory.about.com/cs/godsreligion/a/aa040200.htm
She explains, “The answer is complicated, rooted in two millennia of history, and based partly on the difficulties of calculating dates according to the Jewish calendar, and partly on the desire to forge a new and separate Christian identity.” It is a good article and not overly long or complicated.
For other resources, check out Jimmy Akin, CA Senior Apologist’s Blog, which also addresses your question, here:
jimmyakin.com/was-the-last-supper-a-passover-meal
If you’re up to it, peek at the Wiki article
en.m.wikipedia.org/wiki/Last_Supper
and scroll down to the heading “Time and Place.”