Window for Partial Lump Sum from Cash Balance Plan

[Guest ircreader]

I am aware of a cash balance plan that gives participants who terminated employment vested a 3-month time period to elect a partial lump sum. If the participant does not elect the partial lump sum during the 3-month period, it is forever lost (traditional DB options are available at the earliest retirement age).

I'd like to know if there any other plans that limit the time period when this can be elected.

Is anyone aware of other plans with a similar one-time window for a cash payment?