I called HPD compliance department (yes I did). They referred me to the HPD handbook.
Go to:
http://www1.nyc.gov/site/hpd
Click on the following:
Developer (blue line on the top)
Markating (the the left side)
Then select Markating Handbook
Read page 44 paragraph 3
As required under tax credit rules for all verification, documents must be current within 120 days of the tenant income certification (TIC) effective date (which is ultimately the move-in date).