All your questions, well most of them are answered in previous posts. With regards to tagging, Terry was following his curfew and never removed the tag, hence my question what happened to tag and tracking of it?
His curfew was from 7am-7pm Friday-Sunday for a drink related offence. Therefore he had drink after work on Thursday, day before start of his usual weekend curfew. Thursday night (to Friday morning) is when he disappeared.
I personally think there are much more information available in this case that any other UK cases. Police just need to put all puzzles together and of course to find him for his family and children sake.