Do units still have infinite charge speed bonuses when close to targets?

One thing that constantly drove me nuts were little unwritten bonuses, like infinite charge speed boosts.

For example, if I ran a Black Coach around a Nurgle army, there is about 15 speed difference between plague toads and a Black Coach, yet the toads would get the speed boost of charging and never lose it till they eventually caught the coach.

Did this ever get fixed, where units eventually stop charging and dont just get an infinite speed boost while within range of the target?