I2 + 2e- -> 2I-
SO2 -> SO42- + 2e-
would that be it?
General idea looks OK.
Also, the biggest problem I've encountered when titrating it, is that I think it's an equilibrium reaction, when I add the iodine and mix it, it goes to dark blue/black then back to the original colour; but if i had 50mL of iodine and leave it overnight it returns to the original colour; I'm asking when do i know I've reached the endpoint (using starch as indicator)
Every reaction has some equilibrium. In case of redox reactions equilibrium is almost always so far on the left or right side, that you don't have to worry about. This case is no different.
Iodine color alone can be used for determination of the end point, but it is not clearly visible. However, free iodine adsorbes on the starch and such a mixture has very clearly visible blue color, thus determination of end point is much easier.
You have to add starch at the moment when there is only small amount of iodine present in the solution. Otherwise iodine can bond to starch so strong that your titration result will have systematic error.
Generally speaking iodine/starch endpoints are not my favorites, as they are not as clearly visible as others.
What kind of determination will you do? Will you titrate just with iodine, or will you add iodine excess to sample to titrate it later with thiosulfate?