Impermissible Manipulation of Annuity Starting Date?

[Übernerd]

Plan A has an unusual feature that strikes me as impermissible. If a participant submits a benefit application mid month (e.g., January 7), when the first check is cut (say, February 15), in addition to the full monthly payment for February it includes a "make-up" payment for the fraction of that month from the date the paperwork is submitted through the end of that month (here, January 7 through January 31).

This seems to either (i) violate the requirement that the annuity starting date be the first day of the first period for which the benefit is paid [§ 1.401(a)-20, Q&A-10], by making it the day the paperwork is filed rather than February 1, or (ii) provide for payments for a period before the annuity starting date (which can't be earlier than February 1, as I see it).

Is there some way this is permissible? Thanks.