Why can't Fast analyze images, whole only Thinking can?

Since the last update, Flash and Pro were replaced by Fast and Thinking (model options).

Now, if I use the free version, Fast, when I send an image, it says it can't view the images and has technical issues. When I switch to Thinking, problem is solved.

Before that, both Flash and Pro were capable of analyzing images.

Is this a temporal issue or is image analysis now a paid feature?