I'm not asking this question for me because why would I need to know it? No, not me at all, not even a little bit. But let's say someone needed to know the answer to something to prepare for, say, traffic court. Please advise.
In your considered opinion, when does the speed limit on a roadside sign actually take effect? Is it....when you can first see the sign?
What say you? I'll be sure to tell my friend.