Avatars missing after upgrade

Those images are pointing to Facebook's server. You can investigate by right-clicking on the image > inpsect and look for the src value. Facebook expires and deletes the images after a while.

When the plugin downloads Facebook reviews it tries to save the images to your local server, sometimes this doesn't work for various reasons. You will need to go to the Review List page in the plugin and delete the Facebook reviews. You can then re-download them to update the images. Leave the download pop-up window open for a few minutes after it completes, it should try and copy the reviews in the background.

So you are saying Josh if I delete them in my review list, it will know they are deleted and redownload them.

No, you must go to the Get Reivews > Facebook and re-download them after you delete them. When you do it will update all the images.