DS wants to repeat Year 13

@user20 UCAS offers are generally based on predicted A level grades, not AS grades.

They will look at AS grades if they are available.
Someone only capable of Ds at AS (though aptitude or work ethic) is unlikely to suddenly get up to A grades at A level.

Therefore they won't waste an offer of e.g. AAB to someone with DDD at AS as they are statistically very unlikely to achieve the offer.

I agree with you that L3 qualifications would be useful. But I also don't think repeating y13 is the way to go. For all your son's assurances I think it is likely that the same issues would arise again.

Help him to get a job. Then he can do an evening class/course, and show he now has the work ethic. If he proves he can do this, then consider an access course or apprenticeship for Sept 2020.

(He didn't drop to one A level. As in he didn't officially stop iirc. He was still entered for the exams.)

OK OP now you’re just making things up. I don’t believe the UCAS thing because:
a. It would have been nothing to do with a careers teacher and everything to do with his form tutor/head of 6th Form.
b. They wouldn’t have let him start a UCAS application if he dropped down to 1 subject.
c. most UCAS applications are put in before courses are finished and so teachers put predicted grades. The fact that he hadn’t finished his BTEC is irrelevant. UCAS deadline is in January so very few apply with a solid set of actual grades.

@user20 it’s almost impossible to know what’s true, what you’re making up and what you may believe to be true but your DS has made up.

the careers teacher told him to withdraw his application because he'd get no offers with only 2Ds at AS

What did he apply to do?

OP, I think you are in denial and ignoring what is obvious to everyone else. Your focus seems to be on him achieving A levels as a definition of success in life. It isn't always the case.

Also you seen to acknowledge he isn't mature enough to self discipline and school should have done more but then assume he is disciplined enough to handle a meeting by himself. I think it's really important that you now show him support and guidance.

One other thing OP - I mentioned the Open University above and said that their fees are expensive (they effectively charge the same as other universities despite not having the overheads). However, if your son gets a job, while he's working he could look at the Open Learning website (free) and the Futurelearn website. A subscription to Futurelean for a year costs £200ish and you can do as many courses as you want during the year. There are law-related courses, he could also look at courses designed for people considering university or maybe something completely different will take his fancy or he could try a language. You can do the courses for free, but the certificates cost, so the subscription could definitely be worthwhile. After the year he would have some money from the job, and some new knowledge from the courses.

Of course you can get time off work for a meeting at the school. You request it as emergency leave for a family matter.
It will probably mean losing a days pay (or half a day) but this is IMPORTANT. Would you not take time off work if he was rushed to hospital with a medical emergency?
Take ONE day off work for your son. Please. He needs help.
He also needs to accept it is almost 99.9% likely he won't be going back to 6th. He needs a better plan. The school should have info on what local colleges offer. If he goes to the meeting and says I am interested in doing X but I need to know the best route they will help and advise. If he just goes in and says "I will work harder I promise" then that's no good.
He needs a written 'business plan' of what he would like to do. Just saying "I wanna be a barrister" isn't enough. You need to sit down and look properly at routes and qualifications and skills and even volunteering/internships that could reach that goal. Plan it. Write it down. And get correct advice - whether from school, colleges, a local law firm or whatever. He obviously didn't have much guidance when picking his a level subjects. Geography! Why? Business Studies! Why?
Go to the meeting.
One day off work is nothing vs your son and the help he needs.
Take the day off work!

A levels are not for everyone, even clever folk aren't always suited to them and they are not the only route to success - if he is not motivated enough to study now - it doesn't mean he won't be in the future, I think there is little point in forcing the issue now, he is at a fragile time in his life..he needs help and support to move on to the next stage - a job in tesco is absolutely fine while he figures out his next move...just do not allow him to hang around home doing nothing, it really isn't good for him.

I don't think alevels are the right course for your ds. He hasn't engaged with them.

Post 19 Education is funded by advanced learner loans so it's not the end of the world and he can access it, he just has to pay it back once earning £25k. There are many alternative programmes -

Access to he if he wants to go to uni (law is an option)
End point assessment
Apprenticeships
Vocational options.

This is just some of the options and if he is funding it with an advanced learner loan then he may well have some engagement with it.

Flogging the dead horse that is school alevels isn't going to help aaanyone and as you say, school haven't helped (in fact appear to be a wet lettuce!)

He didn’t turn up for school very often! You need to open your eyes. You’re not helping him, you’re enabling him.

I agree.

I think he feels a bit insecure now that he has no a levels and is worrying that his mistake will see him with no job and out on the streets

The majority of people don't have Alevels and don't end up with no job and out on the streets.

There are options open to him, as posters keep trying to tell you. It's your job as his parent to make sure he's aware of the options so he doesn't feel anxious and think he's going to end up poor and homeless. As your parent you need to help him stay positive and maintain good mental health. Have you even looked at the .gov website to look at local apprenticeships?

Did you answer whether he'd applied to uni at all? A few months ago he could have lined up a foundation year, but I suspect not. I think you did post he's enrolled on a BTEC business course at college. Did you speak to the college about funding yesterday? Because however busy I was at work I would have damn well found the time to make that phone call.

@user20 I already said it would be the person in charge of attendance marking S in the register. Form tutors won’t be doing it at this stage. Yr 11s and Yr 13s will be bulk marked as on study leave from the point it started until the end of term.

@user20 yes of course they have marked him as code S during study leave, duh?!?

Like I said before - if the kids are all on study leave then it has to be recorded on the attendance register as code S which indicates study leave. If they marked him with any other code this would indicate that he wasn't on study leave and was absent.

I'm sure @Bunnylove83 and @EvilTwins know this themselves as I'm sure they've used sims before.

And OP, whoever deals with sims in your DS' school will just bulk mark all the year 11, 12 and 13s using code S at once through the system.

It's not as if your DS' form teacher will mark the register every morning and mark the whole class as S every single day. The registers will already be filled in from the commencement of study leave right through until the end of term so the form teachers don't need to do this as it'll be done for them by somebody else

@user20 attendance code S is the code used for study leave on electronic registers such as sims.

They won't mark him using code O during study leave because of the very fact he is on study leave whether he did one exam or not or revised or not. For them to record him with any other code would be inaccurate because it is study leave and DfE guidelines state that study leave must be recorded as code S.

My DH is a teacher.

"ds is old enough to go to the meeting himself he is not in primary school anymore."

He is old enough, but clearly not mature enough. You seem to think that once a child turns 18 they magically become mature, responsible adults. They don't. Some do, an awful lot don't. You keep saying you are supporting your son, but you aren't.

You keep saying that he needs to step up. Yes he does, but so do you. Your hands off approach hasn't worked so far.

And he's not like that - he will turn up for the meeting

He didn’t turn up for school very often! You need to open your eyes. You’re not helping him, you’re enabling him.

@user20

He's in an in between phase. I think since it is school and not uni you should be involved, especially since you will be supporting him financially.

As for the dentistry he needs to apply for an NHS exemption on grounds of low income.

He needs to be bringing in an income. He could apply for universal credit and get a pittance of around £200 a month (although as spending money for someone living at home it is a lot) and having the job centre breathing down his neck to do 35 hours a week jobsearch till he finds something or working.

Having the basic daily structure of working and some money of his own will do him a lot of good.