(a) When application is filed. The applicant may choose an annuity beginning date by—

(1) Naming the month, day and year in an application accepted by the Board; or

(2) Including with the application a signed statement which tells the date (month, day and year) when the annuity should begin.

(b) After application is filed. After an application is filed, the claimant may choose an annuity beginning date by submitting a signed statement which tells the month, day and year when the annuity should begin.