It seems reasonable to assume that with the change in the reckoning of time among the Nephites- based now upon the signs of Christ’s birth- the first month would be the month in which the sign was given. Mormon’s account indicates that the signs of Christ’s death came on the fourth day of the first month. Since we know that Jesus was crucified in the spring, at the time of the Passover, we concluded that Jesus was also born in the spring, as we have been taught in the restored Church.