We (atc) have to know about your autoland,because the opposite ils on the same runway might be on.This could be for technical or calibration purposes.
Many years ago an A320 almost bit the dust, when the captain did an autoland without telling anyone.The airbus barely made it to the runway in one piece.
It was later found out that the upset was caused by the aircraft crossing the active LLZ of the opposite direction.
So always inform ATC when intending to do a practice autoland.
WWW