Hi there,
I'm a current mature student (in my 30's) studying BSc Adult Nursing. Finances can pay a massive role in influencing your decision, especially since you have a mortgage.
Regarding Student Finance, as I'm unsure of your circumstances, I advise you to look into a Student Finance calculator or contact them directly to see what your options are. In England, we also have the NHS Learning Support Fund, where you get £5,000 per year, non-means tested.
If you already have a degree, then you can apply for an MSc in Nursing, which is typically 2 years from start to finish. Here at LJMU, you must hold an undergraduate degree and have experience in healthcare, which by your post, it sounds like you have those ticked off already. Enquire with Student Finance and the NHS LSF to see what funding is available to you, as this would be the quickest route into nursing.
In terms of the repayment of your student loan, it would be a minimal payment each month. It can vary from how much you would earn, but most barely notice it leave their wages each month.
My advice to you would be to enquire with SF and the NHS LSF, if it comes back that you wouldn't get funding for the MSc, it may be that your apprenticeship is the best financial option at this moment in time. Whether it takes you 2 or 4 years, you'll get into nursing one way or the other, and you need to do what is best for you.
Nat