Given a C corp with a Feb 1st calendar year start. If an S-corp election is made, how are the tax filings handled given the calendar year mismatch.

For example:
C-corp filed for 2/1/11-1/31/12
Employee filed for 1/1/11 - 12/31/12

The Corp has already included Jan/2012 in its 2011 filing.
If the election is made, suddenly the calendar shifts back a month and the corp is handled on the employees/stockholders return. But How is the already covered month of January handled by the employee/stockholders on their 2012 return since it was already filed for by the C-corp?