There is no way to fast forward or rewind by dragging the progress bar in the replay, which is inconvenient. I think maybe we can use a save and load feature in the small-scale battles and campaigns. For example, save the game every ten seconds in the background; then load it when rewinding it. At the same time, increase the maximum speed limit, such as to 64x. Do not render or only render low-resolution above 8x to achieve the fast forward effect.
This may help with reconnecting.