Old Student Debt Dilemma - About to expire/ Statute barred??

Hello,

I have debts from student loans dating back to before 1998. To clarify, I started my degree in 1994 and my understanding is that my loans come under the 'old style student debts.'

I have been deferring these debts every year. I have read somewhere else that after about 25 years or if I am over 50, this debt expires. I contacted Student Loans to clarify when exactly my debts would expire and was told that it would be in 2019. According to her I have an outstanding balance of £9,400, of which £4,100 are in arrears. She explained that the arrears were due to the fact that back in 2014 I had applied for deferral too late and since they can only backdate to three months the rest of the balance would be in arrears. Most worryingly, she also told me that until I clear these arrears the automatic debt expiry would NOT apply to me and the debt would still be outstanding even after 2019.

In light of this, my question is:

1) Is it true that if there are arrears on my old student debts, they would not expire even if they otherwise meet the criteria for expiry (25 years or debtor is over 50 years of age)? Can anyone confirm this?

2) If it is true that my debt will not expire unless I pay off the arrears and since deferment could be regarded as 'acknowledging debt' would I be better of NOT applying for deferment this year? I am considering this option because if I already have arrears anyway I am concerned that deferring it every year would simply prolong the lifetime of this debt.

What would be the consequences if I chose to ignore this and wait for it to become 'statute barred' (potentially another six years from now...)?

Thank you.