See the interesting report about Jesus' Last Suppur appeared in the BBC.
Last Supper not on Maundy Thursday?
Was Jesus Christ’s Last Supper on a Wednesday, and not on Holy
Thursday as widely accepted by the Christians?
Christians mark on the Last Supper on Maundy Thursday, or Holy
Thursday, a day before Good Friday.
A British materials scientist has claimed that The Last Supper of
Jesus Christ was on the Wednesday, and not the Thursday, before his
crucifixion on Good Friday. The Last Supper is the final meal that
Jesus Christ shared with his 12 apostles in Jerusalem before his
arrest, trial and crucifixion.
Professor Sir Colin Humphreys, a scientist at the University of
Cambridge, has made the claim in his book "The Mystery Of The Last
Supper". Prof. Sir Colin along with Oxford astrophysicist Graeme
Waddington, in 1983, identified the date of Jesus Christ’s crucifixion
as the morning of Friday, April 3, 33 AD.
The Biblical scholars have been trying to pinpoint the exact timing of
Jesus Christ’s final meal with his apostles. In the New Testament,
Matthew, Mark and Luke describe the Last Supper as a meal marking the
start of the Jewish festival of Passover. However, John describes it
as taking place before the Passover began.
Another logical problem to the Holy Week model, is that if the Last
Supper was on a Thursday, then for Jesus to have been executed on a
Friday morning, a large number of events had to take place overnight
like his arrest, interrogation, and separate trials before the Jewish
court (the Sanhedrin), Pontius Pilate and Herod. Also, it was against
Jewish law for the Sanhedrin to meet at night.