In a previous Study, after searching all four Gospels for the day Christ was crucified, it was found that all four Evangelists reported that Christ was crucified the Day of the Preparation of the Passover. This is a very important Study, search Brighteon for its Title or click on the Link below:

Passover and the Crucifixion of Christ
https://www.brighteon.com/c9805420-8991-41f0-869f-471e508d37c8

Based on the Law of Moses, the day following the Preparation Day of the Passover is a Special Sabbath for the Jewish People (the first Day of unleavened Bread). It is also reported in the Gospels that after that special Sabbath there was additionally a second Sabbath (read the above study), the regular seventh Day Sabbath (the fourth Commandment Sabbath). Subsequently after these two Sabbaths, disciples of Christ came to the Tomb and found it empty.

The big Question is, based on what is actually written in the Gospels, can it be unequivocally determined the Day when Christ was resurrected?

Let's go to the New Testament and find out!

Matthew 28:1
IN THE END OF THE SABBATH, as it began to dawn toward (epiphóskó) THE FIRST DAY OF THE WEEK, came Mary Magdalene and the other Mary to see the sepulchre.

The verse below is used as a reference to help understand that in the Gospel the same Greek Word epiphóskó is used with a different meaning:

Luke 23:54
54 And that day was the preparation, and the sabbath drew on (epiphóskó).

Epiphóskó was used twice in the New Testament, Matthew 28:1 and Luke 23:54 are the only two instances.

Epiphóskó can also mean: about to begin, draw on, was coming on. In Matthew 28:1, be aware that for the Jewish people the first day of the week begins Saturday at Sunset.

Genesis 1:5
And God called the light Day, and the darkness he called Night. And the evening and the morning were the first day.

You should not discard the possibility that Matthew 28:1 may have actually reported that in the End of the Sabbath, after Sunset at the beginning of the first day of the Week, Mary Magdalene came during the Twilight to the Tomb (beginning of Saturday Evening).

Matthew 28:1 is not the sole controversial verse that may indicate that the Resurrection occurred prior to Sunday Morning. After you read and understand John 20:19 your whole belief in an Easter Sunday Morning Resurrection will be shaken.

John 20:
19 THEN THE SAME DAY AT EVENING, BEING THE FIRST DAY OF THE WEEK, when the doors were shut where the disciples were assembled for fear of the Jews, came Jesus and stood in the midst, and saith unto them, Peace be unto you.

Apostle John who also wrote the great Book of Revelation would never write such an important verse John 20:19 with an error.

"And the evening and the morning were the first day.

Since for the Jewish People Saturday after Sunset is the beginning of the first day of the week, the Evening of the First Day of the Week is Saturday Evening. There is no other way around this, you need to come to the realization that Apostle John wrote that on Saturday Evening Christ appeared to his Disciples.

Don't base your Faith on religious Traditions, don't trust human Traditions.
I recommend to all readers to study the Bible with a sincere heart with the sole objective to uncover the Truth (not to justify some personal Beliefs).

There are online Bible sites with Translations having the Dr. Strong Concordance (Hebrew and Greek Lexicons) to check the meanings of the original Hebrew and Greek words. Seek and ye shall find, God is gracious to guide you to the Truth.