The rule HAS to be your turn is over....
...or we would all need lawyers to play a match.
http://www.google.com/url?sa=t&rct=...08spBy7Lx1Og1F3_N6ySQ&bvm=bv.1355534169,d.aWM
I've had it happen from the bottom of the pocket and from the back
of the pocket.
The British side pockets are brutal...happens a lot at snooker.
Here's another example.