From a casual reading of 3 Nephi, one would assume that the appearance of the Savior occurred not long after the three days of darkness. This concept is reinforced by 3 Nephi 11:1 which states that when Christ came, the multitude had gathered together at the temple and they were marveling and wondering one with another, and were showing one to another the great and marvelous change which had taken place.
However, Mormon gives us the chronology of events when he states that Christ manifested himself to them in the ending of the thirty and fourth year. He had earlier informed us that Christ was crucified during the first month of that year (3 Nephi 8:5). Therefore, there must have been a considerable time period between Christ's resurrection and his appearance to the Nephites. This same verse tells us that it was at least 40 days because he appeared after the ascension of Christ into heaven (see Acts 1:3,9-11).
Bruce R. McConkie
"The Nephites adjusted their calendar so as to begin a new dating era with the birth of Jesus; and according to their chronology, the storms and the darkness and the crucifixion came to pass on the fourth day of the first month of the thirty-fourth year. (3 Ne. 8.) Then 'in the ending' of that year (3 Ne. 10:18-19), several months after the Ascension on Olivet, Jesus ministered personally among the Nephites for many hours on many days." (Mortal Messiah, Book 4, p. 307)
3 Nephi 11 The Savior visits the Nephites
Ezra Taft Benson
"It is clear that 3 Nephi contains some of the most moving and powerful passages in all scripture. It testifies of Jesus Christ, His prophets, and the doctrines of salvation. What a blessing it would be if every family would frequently read together 3 Nephi, discuss its sacred contents, and then determine how they can liken it unto themselves and apply its teachings in their lives!
"Third Nephi is a book that should be read and read again. Its testimony of the resurrected Christ in America is given in purity and beauty." (A Witness and a Warning, p. 43)