Excerpt: Because January 31,2010 is a Sunday, the deadline for Cycle D determination letter applications is extended to Monday, February 1, 2010. Note that some Cycle D plans with fiscal year plan years may make a one-time election to file in Cycle E under a special rule in section IV of the 2008 Cumulative List (Notice 2008-108). Since February 1, 2010 is also the first day of the Cycle E submission period, to avoid confusion as to whether a particular plan is filing under Cycle D or Cycle E, the IRS requests that a plan sponsor of a Cycle D plan filing on February 1, 2010, who is electing to file under Cycle E under this special rule, note this on a cover letter or on the application.