Unreported substitute

[kycat1]

Has the rule on unreported substitute changed a little in the past few years? I have an older case book that I still refer to a lot and it says something different than the rule book does now. Rule book says if an unreported sub bats and reaches 1st safely and the defense reports the unreported sub to the ump before the next pitch, then all runners return to the original bases, the unreported sub is disqualified and is also called out! This is rule 4-6,C,3Now, according to the older case book, all the plays that discribe the same actions does have the player disqualified, but does not call the unreported sub out, but says to have a legal player bat assuming the existing count.
Any thoughts on when this changed???