Firstly, regarding the observable universe there is a certain radius of a circle, and we cannot see further than that. It is understandable, that due to photons travelling at a certain speed we can only see that far. But question is: "What happens with photons that might arrive later to our vision?", meaning outside our "ring" of the observable universe, to my understanding we could detect also photons or radiation coming from there, meaning that our radius of the visible universe is expanding, in the sense of areas now, where we can have layers of certain visibility and with a percentage of "accuracy" and not a static radius, i.e. "x light years beyond the radius the existence of one y object has been confirmed due to late photons coming to our vision. There might or might not be more around it but we have no certainty". Understanding human life is too short to experience that change, these humans might be living some thousands of years from now. Until here I have considered a static model, I haven't taken into account universe expansion yet.
When the universe expansion speed is put into the equation, things change. If the universe expansion is faster than the speed of light, we would be "losing ground" in visibility, meaning more objects would be leaving our radius than the ones coming, however nothing is faster than the speed of light, meaning that the universe expansion is smaller than speed of light (unconfirmed quotation), thus in reality to me, our vision should be expanding, but slower than the static model I described a little earlier.
On the other hand, at the edge of our imaginary ring, we can also have objects popping in and out from time to time. In this manner we can also create an uncertain map of what was and what will be in the outer ring of our observable universe, thus expanding our vision, and over time this map will be more certain.
Now, I haven't done the math, nor am I certain of many of my quotations, so please don't be angry at me, I am just a curious human being trying to learn more about our universe :)