The information provided in SD 19 matches the information given in SD 20 guidance for examiners dated 1998. SD 20 was replaced by the FEH which has been updated a number of times so is the most up to date reference.
Following the 180 degree turn, I ask the candidate to turn again so that they are tracking roughly towards the second turning point but off track, this is an ideal opportunity for fixing their position before initiating the diversion.