It sounds as though the interest applied whilst learning is 3% plus inflation rate of 3 to 4% (lets call it 3%) so actual interest of 6%.
That is going to be compound so the interest will keep adding to the loan until you start repaying it.
Lets say 1k loan, end of year 1 you owe 1060, end of years 2 (assuming no further advance and no payment) £1123.60, etc. etc. until you start paying it off when the interest rate is reduced to the 3% as an incentive for you to pay it.
Imagine someone that borrows 1k and doesn't earn enough to start repayment for 10 years... By that time they would owe £1790.85 (assuming inflation remains constant).
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Shaun
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