Make sure you are well rested and have sorted out as many practical/life issues (that are sortable) as possible in advance. For example, make sure that your living arrangements and finances are in place, and any other practical things that could cause stress if dealing with them alongside your course.

I wouldn't worry too much about doing loads of reading, but a skills self audit might be good, as chickpea suggested. Find out what training and courses might be available to you through the MPhil (i.e. don't spend time and money on honing a skill that is covered in week 2 of the course).

So, in summary, you started a PhD because *other people* said you should, without checking out what the requirements would be. You don't like it and want to quit, but the only thing stopping you is what *other people* might think. So you have come to ask a bunch of strangers what *they* think and to tell you what to do.

Would it be so hard to do what you want (i.e. stop doing the PhD) and make your own decisions? You've not presented any case or reasons for carrying on, so I'm not sure what the big deal is. Generally people who are quitting PhDs are more concerned about the career/financial/employment reference implications than about 'losing prestige'. Are you sure you're focussed on the right issues here?

Others with more experience may be better able to advise, but I would estimate that 6 hours face to face teaching could well equate to 12-18 hours per week actual work depending on how much prep and marking you have to do.

I would definitely look into a small earnings exemption for some of your NI contributions, or you may find yourself rather short.

There's no right or wrong answer here. Either scenario can work out well or badly!

Things to consider:
- Do you know anyone in Cardiff already? If you know no-one then a flat share can be a starting point for making friends.
- How much do you value being able to cook/do laundry etc at your own convenience?
- What is your tolerance level for other people's habits?
- Will you have a regular space in an office for your PhD? If your project is a totally solo effort, you choose to live alone, and you are new to the city, it could become a rather lonely enterprise.

6 hours a week of face to face teaching, or 6 hours in total (prep, contact time, marking....)

Are you a UK student or an international one?

The reason I ask is that standard UK research council studentships are in the region of £13-14K per year (more in London). That you have only been given a stipend of 5K and will expected to do (what sounds like) a fair amount of teaching in order to get any more suggests you are being somewhat short changed.

Do you have an agreement as to how many hours of teaching you will be expected to do? If you go above a certain number you may wish to consider whether a full time or part time PhD is best.

But in answer to your question, it sounds like your teaching earnings would be exempt from income tax as they fall below the personal threshold.

For context, in which country are you based?

In the UK, the policies around these things tend to be more standardised. For example, it is common now that full time PhDs must be completed within 4 years of commencement. Extensions are only granted in the case of extenuating circumstances e.g. illness.

Have you sought any independent advice on this? If you have been working 100 hour weeks for a number of years then I would be very surprised if you do not already have more than enough material for a thesis. I would ask someone to give you an objective, independent appraisal of whether the extra work is really necessary.

Generally it's best if they don't have too many, or else you might not get much support. But I would say it depends on:
(1) how good/available your secondary supervisor is. A good secondary can make up for availability issues with the primary
(2) Is the primary supervisor as senior/busy as they are likely to get? It may be that they have time for you now, but if their group gets bigger or they get appointed to an even more senior role (e.g. an institute director) then their availability is likely to drop off.

Firstly, congratulations on the offer. :)

Secondly, whether you take the offer or not should depend on (i) what your long term goals are (ii) whether this MPhil would help you achieve that goal. In some fields, a masters degree may be more useful than a PhD. In other areas, taking time out may be detrimental to your career. So it really depends on what you're looking to achieve.

It might help to write a list of bullet points of the kind of things you need to get across, and then get someone to check if they are in a sensible order. There needs to be a certain flow of the points you're making so that the person reading it ca n see where you're coming from and going to.

So here’s a made up example….
Dear Professor Smith,
I am a prospective PhD candidate writing to enquire as to whether there are any opportunities arising for graduate study in your department.

During my Masters degree in Foot Studies at the University of Hogwarts, I undertook a research project on the little toe. Through the course of this work I became interested in how the little toe relates to the other toes. Reading around the subject I discovered that your group has done extensive work on the Big toe, and I was wondering if there might be the possibility of developing a project in big toe-little toe interactions.

I attach a copy of my CV with further details of my experience to date. I have been an active member of [such and such extra-curricular academic activity] and would bring this enthusiasm to a PhD project. I would very much value the opportunity to contribute to your department’s work.

Please let me know if it would be possible for me to call or meet you to discuss possible opportunities. I am available to start a PhD in the near future, but I recognise that funded opportunities may take longer to plan, in which case I would be committed to seeing through a funding application process.

Yours sincerely

Jo Bloggs
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There might be a need for a bit more detail about the candidate and his/her experience, or why s/he actually wants to do a PhD but this is a kind of structure that could work. It's just a question of balancing a standard format with expressing your own voice. You don't want to sound too bland, but don't let enthusiasm cause too much informality to creep in either.

On a separate note, before approaching a Prof, you might want to check the quality of that uni's student support systems, especially with respect to any particular issues you may need help with.

Good luck with your application

I think the important thing to remember is that most people find it initially tough to write cover letters and so forth, and even people who have perfect spelling etc are well advised to get a friend to look over their application first.

As you have no prior relationship with the person you’re writing to, it has to be absolutely clear what the purpose of the contact is. Keep the message short but informative, and don’t be presumptive (leave start with talk of funding)

In these kind of situations I usually follow the following kind of pattern
- Introduce myself
- Explain *WHY* I’m getting in touch with that person (the intent of the message)
- Explain why I’m getting in touch with that *THAT* person (as opposed to any old prof)
- Explain why *I’m* getting in touch with that THAT person (i.e. why I’m the sort of candidate that they should be interested in, with supporting evidence).
- Open the channels for further communication

I'll post an example in another post. But it would also be worth you searching online for advice in this kind of thing e.g.