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And there are different practices regarding mourning customs during Sefirat Ha'Omer. There are some who have the practice of forbidding [weddings and haircuts and parties with music] immediately after Pesach until Lag Ba'Omer, and from that point on they permit weddings and haircuts, since according to a midrashic tradition they [ie the students of Rabbi Akiva] stopped dying and 34 days were left. And it would be logical for the prohibitions to remain until the 35th of sefirah, but we say "a little bit of the day counts as the full day" and so it is permissible [to marry and cut hair etc.] on the 34th day but not early. And this is the path of our master the Beit Yosef who writes, "and the custom is not to have one's hair cut until Lag Ba"Omer for it is said that is when they [Rabbi Akiva's students] stopped dying. And one should not take a haircut until the morning of the 34th of sefirah. However, if Lag BaOmer occurs on Friday, then one can cut one's hair on that day out of honor of Shabbat for that is a time of haircuts for the sake of Shabbat." - And these above are the words of Beit Yosef. And he further writes in se'if 3 "some have the custom to take a haircut on Rosh Hodesh Iyyar and it is a mistake for them to do so." Those were his words above. And he meant that according to the custom that these things are permissible after Lag Ba'Omer, the prohibitions must begin immediately after Pesach for they died for the 34 days after Pesach. And if that is so, how could one take a haircut on Rosh Hodesh Iyyar - it's an internal contradiction of two different mourning customs. And what we said about haircuts is the same for weddings for they are all one matter.
(6) Until Lag BaOmer - and "until" includes that day itself, thta is until 33 full days, each one and its night. This is not the case with the 34th day. They were not strict about it except for the nighttime, but once the sun rose in the morning it was permissible because of the principle that "part of the day is like the full day."
(8) "On the 33rd Day" for their maintain that they stopped dying completely on the 33rd day.
(11) But not at night. There are some acharonim who are lenient about haircuts at night and the Elyah Rabbah concludes that nonetheless when it comes to weddings we do not see anyone who is lenient except for on the 33rd day itself and not on the night preceding it. However, when the 33rd of the Omer is on Friday and it is hard to do during the day it is possible to be lenient and to get married on the night before.