I am currently in my 3rd and final year of my BSc and have approx. £39,750 of student debt.

I will be studying for an MSc part-time for 2 years that's being paid for by a company who I will work for 4 days a week.

I am under plan 2 for student debt repayment, which means I pay 9% on everything I earn over £2274 a month before tax and other deductions. I have not received my formal offer for my salary for my job yet, but I anticipate it will most definitely be under this threshold for two years.

While I am studying, my interest will be at 5.6%, and thereafter if my earnings are over £27,296 it will also be 5.6%.

When combining this with a postgraduate loan:

You pay back 6% of your income over the Postgraduate Loan threshold (£404 a week or £1,750 a month). In addition, you’ll pay back 9% of your income over Plan 2 threshold (£2274) (undergraduate one outlined above).

The crux of my question is, since this debt gets written off after 30 years, would it be worth taking out an extra masters student loan and put that in my investment account/use it to cover extra expenses? I may be thinking of this completely wrong though.

More info: I will be living with my parents for at least 1 year after finishing my undergraduate, so will be saving a fair amount of money. The main expense will be selling my current vehicle and purchasing a different one more suited to the commute involved.

Any help is appreciated, apologies for more details and happy to answer anything else.