My mistake. I meant "crucifixion" and wrote "resurrection" instead. Mornings are not kind to me.
John placed Jesus' death at around the time the Passover lambs were being slaughtered (John 18:28; 19:14, 31, 42), before the Passover meal (obviously). The Synoptics place his death the day after the Passover meal (Matthew 26:17-20; Mark 14:14-17; Luke 22:7-14).
Is this just a case of "personal, subtle observations being different?"
And there are many cases of deliberate changes (not including the innumerable accidental mistakes) throughout biblical texts. The interested reader is referred to The Orthodox Corruption of Scripture: The Effect of Early Christological Controversies on the Text of the New Testament, by Bart D. Ehrman.
Bed time.
Not correct, my friend. Passover itself lasts for ONE WEEK. The "preperation day" referred to in John 19: 14, 31, 42 AND Matt. 27:62 AND Mark 15:42 AND Luke 23:54 is a FRIDAY, the day before the SABBATH, which to all Jews is Saturday. "Preperation Day" is every Friday to a devout Jew even to this day. The seven day period of the "eating of unleavened bread" is found in Ex. 23:14. The reference in John 18:28 was for the Temple Guards not entering the Praetorium. This was to prevent them from becoming "defiled" by contact with Gentiles, which would have required a heavy purification ritual prior to being able to offer and eat unleavened bread in the Temple during the remaining days of the "Feast of Unleavened Bread". Your confusion probably stems from equating the ritual eating of the seder with the entire Passover holiday. Not correct.
You may want to read the original source material, cover to cover, and not rely on the highly flawed "analysis" available on infidels.org.