; or (B) one-half of the rate of the salary payable to an immigration judge during such period if before he retired he had served as an immigration judge less than 10 years. Such retired pay shall begin to accrue on the day following the day on which his salary as immigration judge ceases to accrue, and shall continue to accrue during the remainder of his life. Retired pay under this subsection shall be paid in the same manner as the salary of an immigration judge. In computing the rate of the retired pay under paragraph (1) of this subsection for any individual who is entitled thereto, that portion of the aggregate number of years he has served as an immigration judge which is a fractional part of 1 year shall be eliminated if it is less than 6 months, or shall be counted as a full year if it is 6 months or more. In computing the rate of the retired pay under paragraph (1) of this subsection for any individual who is entitled thereto, any period during which such individual performs services under subsection (c) on a substantially full-time basis shall be treated as a period during which he has served as an immigration judge. (i) Election To receive retired pay Any immigration judge may elect to receive retired pay under subsection (h). Such an election— (1) may be made only while an individual is an immigration judge (except that in the case of an individual who fails to be reappointed as immigration judge at the expiration of a term of office, it may be made at any time before the day after the day on which his successor takes office); (2) once made, shall be irrevocable; (3) in the case of any immigration judge other than the chief judge, shall be made by filing notice thereof in writing with the chief judge