No need to set back the clover. I've spread everything from WR to peas to oats into clover with great results. I wouldn't want to set back with spray or mowing my clover especially in the fall. If you want, you can overseed when clover is stressed late summer and not as thick, or late fall when it has been browsed heavy. I overseed either mid Aug to early Nov and usually more so the latter date depending on the weather. . Again if can do before a rain certainly helps. T&M is a bit of a learning curve and you just have to play till you get the hang of it and change expectations of what the field will look like and its pace of growth. Also easier to do no till if severall seasons of rotations have been done to get the soil at more ideal conditions. We are in day 58 with no rain so my plantings not already in ground are on hold.