Why are people stating ‘no 19 year old does this/that’? There are 19 year olds and 19 year olds. It’s completely plausible that this one might choose to spend time with his step dad at weekends. Maybe he struggles socially and has no friends or hobbies?
Well it's not weekends , the OPs BF has different days off each week. And yet his step son is still supposedly there with him for the 48 hours solidly. So much so that he can't even make a phone call or send a text.
And no one on the thread believes this because many of us have teenagers who are at college / university and none of them behave like this. And presumably this lad was at school until recently and yet he still had this odd timetable of being off school for any two days that his former step dad was off work.
So yes, it's odd to have a school AND a university course that gives you two days a week off but different days each week depending on your former step dads shifts. This lad is probably at the only school in the UK that does this and then, by complete coincidences at the only university course in the U.K. that also does this.
And then, in another huge coincidence, he's the only 19yo in the UK who has no friends, hobbies, interests and spends no time online. And on the days he sees his former step dad they do things all day every day and all evening.
Oh and he used to live with his grandparents but now he lives with his mothers former partner but he's never lived with his mother or his father.
So all in all a very unusual set up.
That's why people don't find it plausible.