as becoz the Manual Form filled by you duty signed by CA & you & also stamped by the ICAI... that may be possible at the time of feeding by the employee of ICAI he wrongly filed 02.02.2012 instead of 04.02.2012.
and if you check the date of your 3.5 year of training it completes on 04.02.2012.
I think at the time of articleship registration you have received a registration letter form icai in which the starting and ending date shall be clearly mentioned.
You should go by the date.
If any problem occurs in the future ,what u hv to do ,is to show the letter you got from ICAI. and that's all.
If it was data feeding fault or something else then it was the fault of ICAI not of your's.