[Jewbacca]

Passover in Israel is 7 days, not 8.

The eighth day was added during the Diaspora because of concerns that local calendars/times might be off.

[D Rider]

Seems like a wordy way to say that a Friday crucifixion is impossible since the sabbath following a passover is a high sabbath, and a high sabbath never falls on a regular sabbath. And the scripture records this when Joseph of Aramathia asks Pilate for Jesus’s Body...etc.

[Pmary65]

The Jewish Historian Josephus (~70 A.D.) The Antiquities of the Jews , Book 2 Chapter 15 Line 315-7 says; “So the Hebrews went out of Egypt, while the Egyptians wept...it is that in memory...we keep a feast for eight days.”
As well for the benefit of the dispersed community,a diaspora Passover period was introduced later around 360 C.E. by the famous Jewish Mathematician - Astonomer Ben Hillel II. He correctly regulated the 19 year metonic (lunar-solar)cycle calendar with intercalary months and lengthened the various feast periods with Passover extending to Nisan 22nd.

[tang-soo]

I think the 8 days is from two different festivals. 1 - The Passover (1 day) and 2 - The feast of unleaven bread (7 days). the two have been combined into one observance called Passover.