I believe it can be any amount. The 402(g) limit cashout provision is meant to give an employer discretion to overide an election. If the plan provides that a cashout must occur, there is no limit from what I can see.
Let me take it another step further. Some of my pre-409A plans provided that installments, regardless of election, must always equal at least 1/2 of the 415 DB limit as in effect on January 1. It was a way to assure participants (and plan sponsors) that the distributions would not be painfully small, and that they would also provide a reasonable income supplement. This is certainly a definite and pre-determined schedule. Whether it works under the regulations is a bit unclear to me. Getting an answer before this ridiculous semi-compliance date of 12/31/07 is problematic.
George