Hello - ten years since I finished mine.
I would say what are your career ambitions, as a PhD can be a millstone round the neck as employers don't always understand and can make you overqualified for most jobs. It can be highly stressful, tearful, and awful at times, but the sense of achievement once you almost give birth to your thesis is amazing. By the end you're the expert in that small area of work you have chosen.
Workload - my supervisor told me from the start she expected the equivalent of a full time job, how and when I did the work was upto me. So if I wanted to start at midday and work until 8pm each day that was fine. I worked weekends often, and when in the field I only took one day off as so busy and maximising my time.
When I did mine I spent the first six months doing a literature review followed by another six working out what techniques and direction my research would ultimately take. I spent the next 18 months or so doing my research and then writing it up. Although my supervisor and team (which were at another university as part of a larger project) were invested in my research, I was left on my own to do so but giving regular feedback to them. My university had an annual day where PhD students gave an update to the department and anyone else interested a chance to come along like a mock conference. We also had to do the equivalent of thirty days training over three years, so could be a CPD course or method you wanted to learn for your research for example.
As above I had two supervisors, but my second had no interest after he was told he was not coming to Italy. I had regular meetings with my supervisor, the university I did it at made it a rule you had to have 12 meetings per year (emails did count if overseas doing fieldwork). We also were expected to live within 10 miles of campus, and they were cracking down on it as many of my peers were not!
Teaching depends on the university and department, I taught every year of mine on different modules but not always related to my research and had to claim the payment back, so wasn't a reliable source of income. Payment of studentship (if research council like mine was) could be quarterly or monthly, mine tried quarterly as was tradition but went over to monthly (which helped with budgeting). 15k could be a research council (ie studentship) so government funded, or could be from your department.
Anything else, please just ask
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