It might sound stupid but after creating vrmap can I move my light and render using vrmap or I have to recreate agian vrmap for frames where I moved light?
Normally you would have to rerender the frames where the light was moved.
-dave
You can if you want to, but it will look weird. If you don’t move it much you might get away with reusing the map.
Usually if you move a light, change its intensity, change of materials or something else, can disturb the IRmap and artifacts will appear. You can look at the online tutorials in the Login page - there you can find a tutorial about Irmaps where you can understand why after you move a light you have to recalculate the solution. 
if you were an abstract artist go ahead and move it all you want. would be very interesting to see heheh