The people talking about consent are treating it like there wouldn't be any legal implications if the university were, for example, to disclose something in the discussion that the student later decided they did not like being disclosed (a previous fail not known to parents, academic problems, health problems etc.).
Exactly. It is not possible for a student to tick a box upon entrance - we have to be much more careful than this. My university's policy - to comply with the law - is that the student should be present when we discuss with parents, so that the student can explicitly control what is disclosed to parents.
Staff are under huge pressure to publish research papers throughout the year and often spend the summer months involved in research activities so holding resits in September is fairly common especially in a research led Uni.
Research is NOT the reason that resits are held at the end of the summer. The administration for the main examination period does not finish until the end of June with graduation in July. The administrators are incredibly busy until the end of July preparing degree transcripts, certificates, writing letters to those who failed telling them the next steps etc. August is then spent preparing the resit exams, printing them, setting up timetables for the resits, sending papers to external examiners to scrutinise etc.
The end of August is the first available opportunity for the resits to happen. Academics have to miss research conferences to come back for resits. The exams are then marked very quickly indeed, so that the results are communicated several weeks before the next semester starts.
I have never ever seen a student who works reasonably fail a resit - the threshold for a pass is usually only 40%, which should be accessible to anybody who has been following the course, after revising over the summer.