Wouldn't yield a significant differenceJust for curiosity sake, wouldn’t it be more than 1258?
For example, pretend the pockets are corners and not pockets. You place the cue ball tight to a corner. Now move it a microscopic distance from the side rail, but still on the short rail. Then continue that microscopic movement all the way down the rail until you touch the other side.
Those are all different positions that ball could land in and be touching the rail.
Now you have to move it away from the short/end rail a microscopic distance. And then start working backwards.
Wouldn’t that equate to a ridiculously high number that’s not just as simple as 1258 positions?
Bigger consideration is the additional space balls take up when they are less than a balls width apart from each other and/or the rail.