1,911. A Get After Maamar
Yibum v’Chalitzah 5:4
If a yavam performs maamar with his yevama and later gives her a get, he cancels what he did and the yevama is free to perform yibum. The Rambam says that it seems to him that she is only able to perform yibum with the other surviving brothers, not with the one who performed maamar.
Yibum v’Chalitzah 5:5
If a yavam gives his yevama a get to sever the levirate bond rather than to cancel the maamar, he disqualifies her from performing yibum both with him and with any other brothers. He must give her another get to cancel the maamar and they must perform chalitzah to enable her to marry someone else.