w3 total cache

In Browser Cache tab, I have ‘Expires header lifetime’ set to 31536000 seconds (1 year)

I have replace an image on my website with another one, but I cannot see the new image when I browse to new site. I guess this is normal behaviour.

However, when I execute ‘Update media query string’, I would expect this to force the client browser to get the new image. But I can see that the number after the ‘?’ does not change. Do I need to purge the page cache for that ?